UK F-35B Lost

[SpazSinbad]

Someone asked about QE ski jumpy & F-35Bs (can't find 'someone' post again). The PDF above has lots of info with this snippet in there also:
Carrier countdown 30 June 2014 Tim Robinson
“...Not your father’s ski-jump
The QE-class’s ski-jump, too, has been carefully designed and engineered from the beginning — drawing on BAE’s Harrier heritage. Says Atkinson: “We had to go back into the archives and talk to people who had actually been involved with trials with the Sea Harrier and Harrier to make sure we understood the history of ski-jump ramp development. The aircraft carrier ski-jump is a UK innovation and something the UK is very proud of.” The QEC’s ski-jump is longer (200ft) than the Invincible class (150ft) and designed so that the aircraft has all three (including the nose) wheels in contact right up until the point where the aircraft leaves the deck — giving positive nose wheel authority throughout. Additionally, the F-35Bs smart flight control system ‘knows’ when it is going up a ramp and will pre-position the control surfaces and effectors to launch at the optimum angle to avoid pitch-up or down....” http://aerosociety.com/News/Insight-Blog/2300/Carrier-countdown
_______________________________

Sea Breezes - Guy Norris -AVIATION WEEK & SPACE TECHNOLOGY/OCTOBER 26-NOVEMBER 8, 2015
"...the F-35’s automatic lift system control will make operations from the ramp simpler and safer, says Wilson [BAe Systems lead f-35B Stovl test pilot Peter “Wizzer” Wilson]. “It has become remarkably simple, thanks to the cleverness of the airplane,” he adds. For a ski jump takeoff the pilot lines up, advances the throttle and maintains alignment with the main nozzle fully aft. When the ramp is reached, rate sensors on the aircraft recognize the change in attitude and deploy the nozzles to the appropriate vectoring angle. Once airborne, weight-on-wheels sensors signal the flight control system to reconfigure the aircraft for up-and-away flight...."

[oldmansquipper]

Ditto: MB did their stuff - c10secs from rockets to splash with full canopy deployed.
:ok:
SP: it’s what they do..and always have done!:D

Tuc: Can we file this one under ‘Seaworthiness’? 😉

[oldmansquipper]

Bu**er the £100M. The pilot is safe. And well done Martin-Baker who, 3 years ago in court, were accused by MoD and the HSE of not understanding how their designs work. This incident made it 7662 aircrew and families who disagree.


abso - bloody - lutely!

👏

[aeromech3]

I had resisted questioning the hypothesis that an engine intake blank was missed in the preflight: from my experience which includes civil versions of military jet engines: I would expect there is FADEC on the F-35, then during start, an over temperature, EGT, would have been avoided, but it would be in the high region and doubtful the FADEC would have continued the start; typically due the lack of mass airflow the N1 and N2 speeds would rise quickly and even if this blank only caused a partial airflow blockage, the engine would undoubtedly surge (reversal of airflow) before reaching any power level to commence a take-off roll.
I propose a loss of a sensory input to the FADEC such as that normally created by forward velocity is more likely, possible some pitot type blank/plug would have limited the engine thrust during the roll; an instance I had to investigate due an aborted take-off was post a fuel control change on an RB211, the rubber gasket of a transit blank had been inadvertently missed, for a sensor pipe connection and, as the post FCU change only called for a flight idle run it was not until the aircraft started its take-off roll, that the engine failed to make take off EPR.

[melmothtw]

"...designed so that the aircraft has all three (including the nose) wheels in contact right up until the point where the aircraft leaves the deck..."

Not really that important to the current debate, but I can't think of a ski jump design whereby all three wheels wouldn't be in direct contact all the way to the end of the deck.

[charliegolf]

Not really that important to the current debate, but I can't think of a ski jump design whereby all three wheels wouldn't be in direct contact all the way to the end of the deck.

Or 4 even!:E

CG

[melmothtw]

Er, the F-35B has three wheels.

[andytug]

Not really that important to the current debate, but I can't think of a ski jump design whereby all three wheels wouldn't be in direct contact all the way to the end of the deck.

I guess if the aircraft starts to rotate more than the gradient of the ski jump at any point the nosewheel(s) might leave the ground? So they design to avoid that.

[airsound]

Pompey News (Tom Cotterill) says they've found the wreckage.
https://www.portsmouth.co.uk/news/defence/royal-navy-in-a-race-against-time-with-the-russians-to-recover-crashed-f-35-after-wreckage-is-found-in-the-mediterranean-3478067

RECOVERY teams hunting for an F-35 which crashed moments after taking off from HMS Queen Elizabeth have found the wreckage of the stealth jet, MPs have been told.
top officials from the Ministry of Defence have revealed that they know the location of the £100m jet – but are in a race against time with the Russians, who are eager to secure the secretive tech inside the F-35.

airsound

[Courtney Mil]

Spaz,

Did you feel a marked, noticeable increase in thrust between MIL and MAX and did you find that the wind up time between 35% and “full” power was a recognisable period?

[Buster15]

I had resisted questioning the hypothesis that an engine intake blank was missed in the preflight: from my experience which includes civil versions of military jet engines: I would expect there is FADEC on the F-35, then during start, an over temperature, EGT, would have been avoided, but it would be in the high region and doubtful the FADEC would have continued the start; typically due the lack of mass airflow the N1 and N2 speeds would rise quickly and even if this blank only caused a partial airflow blockage, the engine would undoubtedly surge (reversal of airflow) before reaching any power level to commence a take-off roll.
I propose a loss of a sensory input to the FADEC such as that normally created by forward velocity is more likely, possible some pitot type blank/plug would have limited the engine thrust during the roll; an instance I had to investigate due an aborted take-off was post a fuel control change on an RB211, the rubber gasket of a transit blank had been inadvertently missed, for a sensor pipe connection and, as the post FCU change only called for a flight idle run it was not until the aircraft started its take-off roll, that the engine failed to make take off EPR.

I guess that you are referring to a P Total pressure input which would increase with forward speed.
That being the case, I would not expect P Total pressure to increase by that much because forward speed would not be that high for this type of take off?

[mickjoebill]

Following an ejection, do any of the aircraft systems make inputs to control surfaces or engine thrust?

Mjb

[tartare]

Of course.
CMD avoid school/orphanage/hospital\\ :E

[SpazSinbad]

Some of the 'red bits' may have come from the ejection seat bits, the parachute box for example?

F-35 MB US16E Ejection Seat Tests 1-8 Slow Motion Long Play [10min - Timely SWEET Child]

https://www.youtube.com/watch?v=bz_Pc03Y5zI
https://cimg6.ibsrv.net/gimg/pprune.org-vbulletin/1680x1050/ejectionzerozerof_35videostillredparachutebox_b05ff55484fc83 2f56117bd2a2866cfa8b4a61b0.jpg

[gums]

Salute!

@ Mickjoe......
The F-16 flight control system remains operational after an ejection unless its failure was the reason to punch out. When the EPU running and residual hydraulics, the sucker will maintain wings level and finally reach the AoA limit and continue. One plane did that and only had one broken main gear upon "landing". Was an aborted dead stick attempt and pilot decided to get out.

We also had anoyther one when the motor went tits up and the family model folks had a fee seconds to coordinate their ejection. The instructor said it was intersting to look down between his legs while in the chute to see the plane continue st ahead and finally hit the desert.

Gums sends...

[aeromech3]

Buster 15 "I guess that you are referring to a P Total pressure input which would increase with forward speed.That being the case, I would not expect P Total pressure to increase by that much because forward speed would not be that high for this type of take off?"
Most modern jet engines would have a temperature sensor, static and dynamic port in their intake, for fuel control and EPR but not necessarily for indication.
Though a classic EPR case would have been Air Florida Flight 90 crash (note: I'm not calling it an accident).

[Buster15]

Buster 15 "I guess that you are referring to a P Total pressure input which would increase with forward speed.That being the case, I would not expect P Total pressure to increase by that much because forward speed would not be that high for this type of take off?"
Most modern jet engines would have a temperature sensor, static and dynamic port in their intake, for fuel control and EPR but not necessarily for indication.
Though a classic EPR case would have been Air Florida Flight 90 crash (note: I'm not calling it an accident).

Thank you.
Yes, I do understand that modern gas turbine engines have very sophisticated control laws and schedules, based upon a series of data inputs, both static and dynamic.
But normally, these would have been designed to be fail safe, such as having duplicate probes or sensors and in the event of an anomaly, these would revert to safe values.
This would be especially important during the critical take off phase.

[armchairpilot94116]

Quite, but there is a big difference between an ejection at 30,000 ft and one at 30ft in where the aircraft impacts and how far it travels thereafter. COSPAS/SARSAT might have provided an indication of the point of seat separation, but that is all. As for the expected overwatch, some of that may be sub-surface (we won't know) and surface vessels are unlikely to be directly over the site. The point is that Wallace - or whoever briefed on his behalf - has removed much of the ambiguity that would have been helpful in delaying the efforts of other 'interested parties' to locate the wreckage.
it’s possible the Russians could just ask the Chinese who might have almost all the diagrams of the plane already

[Trim Stab]

Someone asked about QE ski jumpy & F-35Bs (can't find 'someone' post again). The PDF above has lots of info with this snippet in there also:
Carrier countdown 30 June 2014 Tim Robinson
“...Not your father’s ski-jump
The QE-class’s ski-jump, too, has been carefully designed and engineered from the beginning — drawing on BAE’s Harrier heritage. Says Atkinson: “We had to go back into the archives and talk to people who had actually been involved with trials with the Sea Harrier and Harrier to make sure we understood the history of ski-jump ramp development. The aircraft carrier ski-jump is a UK innovation and something the UK is very proud of.” The QEC’s ski-jump is longer (200ft) than the Invincible class (150ft) and designed so that the aircraft has all three (including the nose) wheels in contact right up until the point where the aircraft leaves the deck — giving positive nose wheel authority throughout. Additionally, the F-35Bs smart flight control system ‘knows’ when it is going up a ramp and will pre-position the control surfaces and effectors to launch at the optimum angle to avoid pitch-up or down....” http://aerosociety.com/News/Insight-Blog/2300/Carrier-countdown
_______________________________

Sea Breezes - Guy Norris -AVIATION WEEK & SPACE TECHNOLOGY/OCTOBER 26-NOVEMBER 8, 2015
"...the F-35’s automatic lift system control will make operations from the ramp simpler and safer, says Wilson [BAe Systems lead f-35B Stovl test pilot Peter “Wizzer” Wilson]. “It has become remarkably simple, thanks to the cleverness of the airplane,” he adds. For a ski jump takeoff the pilot lines up, advances the throttle and maintains alignment with the main nozzle fully aft. When the ramp is reached, rate sensors on the aircraft recognize the change in attitude and deploy the nozzles to the appropriate vectoring angle. Once airborne, weight-on-wheels sensors signal the flight control system to reconfigure the aircraft for up-and-away flight...."

Thanks Spaz - very interesting answer thank you. And it does explain what was going on with the rear nozzle during the launch. The coding involved in controlling that (which is just a tiny part of the mission!) must be horrendous, with the added burden of multiple catastrophic failure scenarios given all the electro-mechanical sensor inputs and high-load mechanisms required. Almost seems pointless to have made the F35 habitable...

[SATCOS WHIPPING BOY]

it’s possible the Russians could just ask the Chinese who might have almost all the diagrams of the plane already
Alternatively they could do what they were good at during the Cold War.
Find someone who has peripheral access to key material, who has no regard for security procedures and who is seriously compromised already.
Now who fits that bill? Oh yes, whoever leaked that video.

[Auxtank]

it’s possible the Russians could just ask the Chinese who might have almost all the diagrams of the plane already

Tell me, is there a living to be made from being utterly deluded?

Asking for a friend.

[charliegolf]

Tell me, is there a living to be made from being utterly deluded?

Asking for a friend.

It's only deluded cos we know they'll say no.

[LateArmLive]

Tell me, is there a living to be made from being utterly deluded?

Asking for a friend.

Speaking of deluded...
Yep. I'm going to put myself out there and say - cause; Mechanical Failure.

[Auxtank]

Speaking of deluded...

I must concede;
touché

[Techo27]

Buster 15 "I guess that you are referring to a P Total pressure input which would increase with forward speed.That being the case, I would not expect P Total pressure to increase by that much because forward speed would not be that high for this type of take off?"
Most modern jet engines would have a temperature sensor, static and dynamic port in their intake, for fuel control and EPR but not necessarily for indication.
Though a classic EPR case would have been Air Florida Flight 90 crash (note: I'm not calling it an accident).
Sorry guys, the fuel control system of any gas turbine engine requires 5 basic inputs for self control either by FADEC or the Fuel control unit itself. These are a reference of PT2 and TT2 for air density, N2 Rpm, Throttle position and PB (Combustion chamber pressure) to prevent engine stall during acceleration. Supersonic aircraft need one additional control factor and that is MA (Mach number) to prevent excessive air entering the engine intake when aircraft airspeed is above Mach.
All other parameters such as N1 Rpm, TIT, FF, PT7 or Oil Pressure are simply for indication to the pilot of the state of his engine EG N1 RPM or PT7-PT2 when converted to an EPR is used to inform the flight crew how much power the engine is producing with FF used as a cross reference. OIl pressure and TIT is simply to inform the aircrew on the state of the engine in regards to oil pressure and operating temperature. Some FADEC systems are designed with software to control any condition outside normal, by warning the aircrew and automatically retarding fuel flow to prevent engine over speeds and over temps and also relight the engine if it flames out during aggressive maneuvering or abnormal atmospheric conditions if throttle position is in flight idle or above.

[Buster15]

Sorry guys, the fuel control system of any gas turbine engine requires 5 basic inputs for self control either by FADEC or the Fuel control unit itself. These are a reference of PT2 and TT2 for air density, N2 Rpm, Throttle position and PB (Combustion chamber pressure) to prevent engine stall during acceleration. Supersonic aircraft need one additional control factor and that is MA (Mach number) to prevent excessive air entering the engine intake when aircraft airspeed is above Mach.
All other parameters such as N1 Rpm, TIT, FF, PT7 or Oil Pressure are simply for indication to the pilot of the state of his engine EG N1 RPM or PT7-PT2 when converted to an EPR is used to inform the flight crew how much power the engine is producing with FF used as a cross reference. OIl pressure and TIT is simply to inform the aircrew on the state of the engine in regards to oil pressure and operating temperature. Some FADEC systems are designed with software to control any condition outside normal, by warning the aircrew and automatically retarding fuel flow to prevent engine over speeds and over temps and also relight the engine if it flames out during aggressive maneuvering or abnormal atmospheric conditions if throttle position is in flight idle or above.
​​​​​​
Firstly, not sure why you are saying sorry. Your post is interesting.
Probably the most important parameter on a very modern Gas Turbine engine as far as control would be Turbine Entry Temperature, or actual Turbine Blade Temperature in the case of optical pyrometer sensor (RB199 & EJ200).
That would be to limit fuel flow as the temperature reached a limiting value.
It would also provide for surge indication in the event of cooling flow interruption.
So, TIT assuming you mean Turbine Inlet Temperature is far more than just an indication to the pilot.
It would be an essential control parameter.

[stickstirrer]

I am no STO VL or F35 specialist but ex FJ Question;
surely at the start of the roll it must have been obvious there was little or no forward thrust? From the video he could have aborted half way up the ramp he was going so slowly.
With all the Harrier experience in the UK surely there must be some early go no go speed/power/accel point? Just asking….

Genuine question.
You're the driver - and for whatever reason all engine temps and pressures look normal as you taxy to the departure point.
Do we know if this was a short rolling take off in STOVL mode or was it using the ski-jump?
How could you not see some sort of thrust anomaly as you powered up - just before rolling to take off?
You'd see it, hear it and feel it... wouldn't you?

[GlobalNav]

Tell me, is there a living to be made from being utterly deluded?

Asking for a friend.

Yes, but you must relocate to southern Florida.

[Jetstream67]

As I said a while back with a serious thrust anomaly (even if for some reason not immediately noticed) the F35 would likely eject the pilot - as designed to - as soon as the 'wheels off the ground flag' switched the protections onto the 'low altitude, can't fly or hover' page.

It is curious that such a smart jet couldn't refuse or abort the take-off and save HMG a few quid but I'm sure they will have fished it out and filled it with dry rice shortly . .

[LateArmLive]

As I said a while back with a serious thrust anomaly (even if for some reason not immediately noticed) the F35 would likely eject the pilot - as designed to - as soon as the 'wheels off the ground flag' switched the protections onto the 'low altitude, can't fly or hover' page.

It is curious that such a smart jet couldn't refuse or abort the take-off and save HMG a few quid but I'm sure they will have fished it out and filled it with dry rice shortly . .

The auto-eject does not function as you state.

[Cat Techie]

Sorry guys, the fuel control system of any gas turbine engine requires 5 basic inputs for self control either by FADEC or the Fuel control unit itself. These are a reference of PT2 and TT2 for air density, N2 Rpm, Throttle position and PB (Combustion chamber pressure) to prevent engine stall during acceleration. Supersonic aircraft need one additional control factor and that is MA (Mach number) to prevent excessive air entering the engine intake when aircraft airspeed is above Mach.
All other parameters such as N1 Rpm, TIT, FF, PT7 or Oil Pressure are simply for indication to the pilot of the state of his engine EG N1 RPM or PT7-PT2 when converted to an EPR is used to inform the flight crew how much power the engine is producing with FF used as a cross reference. OIl pressure and TIT is simply to inform the aircrew on the state of the engine in regards to oil pressure and operating temperature. Some FADEC systems are designed with software to control any condition outside normal, by warning the aircrew and automatically retarding fuel flow to prevent engine over speeds and over temps and also relight the engine if it flames out during aggressive maneuvering or abnormal atmospheric conditions if throttle position is in flight idle or above.

The FADEC also had a slight problem in this case. P2 / P3 / P6 / N2 /T6 were all going out of normal parameters with an enging that would have been seeing its compresser and turbine stages rapidly chewing themselves up on parts of itself and a rogue intake blank. While myself and a colleague were waiting to ground run a small regional airliner today, we discused the accident in question and realised that an F35B was 7000 Kgs more than our airliners MTOM. Our highly effective brakes on 4 wheels wouldn't stop our aircraft from the distance from engine failure to end of deck at the same speed. The F35B brakes certainly could not.

[Mogwi]

I am no STO VL or F35 specialist but ex FJ Question;
surely at the start of the roll it must have been obvious there was little or no forward thrust? From the video he could have aborted half way up the ramp he was going so slowly.
With all the Harrier experience in the UK surely there must be some early go no go speed/power/accel point? Just asking….

With the SHAR, by the time you noticed something was wrong you were going off the end - one way or another. Just no time (or brakes) to stop.

Mog

[hoodie]

The FADEC also had a slight problem in this case. P2 / P3 / P6 / N2 /T6 were all going out of normal parameters ...
How do you know this?

[Buster15]

How do you know this?

Good question. I would be interested in the response.

[LateArmLive]

How do you know this?

I believe it's called absolute speculation.

[NutLoose]

The FADEC also had a slight problem in this case. P2 / P3 / P6 / N2 /T6 were all going out of normal parameters with an enging that would have been seeing its compresser and turbine stages rapidly chewing themselves up on parts of itself and a rogue intake blank. While myself and a colleague were waiting to ground run a small regional airliner today, we discused the accident in question and realised that an F35B was 7000 Kgs more than our airliners MTOM. Our highly effective brakes on 4 wheels wouldn't stop our aircraft from the distance from engine failure to end of deck at the same speed. The F35B brakes certainly could not.


First off to your earlier query I just read, when did I last run a gas turbine, probably several months ago, when did I last run an aircraft, several this month, type ratings about 300 types and engines, also C certifying and last issuance, 3 ARCS this month as a CAMO (Nov).

As for engine indications of an imminent failure, from experience of an IGV failure on an engine reported as slow to accelerate, none or milliseconds before it all let loose and the turbine departed rearwards, First indication aircraft shaking so much you couldn’t see the instruments in front of you, followed by fire warnings, unresponsive to throttle movement and only stopped when the fuel was chopped. Every case is different.

Any update on the recovery now it’s been located?


.

[PlasticCabDriver]

Didn't happen on my watch. Spent yonks sitting in the back of a Puma going nowhere, just in case. Never lifted once, alhamdulillah.

Spent many hours in the front waiting too. Well not actually in the front, in the back too, but would have been in the front shortly afterwards.

[RAFEngO74to09]

Sailor arrested after F-35 aircraft carrier crash video leak (ukdefencejournal.org.uk) (https://ukdefencejournal.org.uk/sailor-arrested-after-f-35-aircraft-carrier-crash-video-leak/)

[MightyGem]

EXCLUSIVE – A credible source, wishing to remain unnamed, has confirmed that an arrest has been made in connection with the leaked footage of an F-35 crashing on take off from HMS Queen Elizabeth.

So, someone has leaked information about someone else being arrested for leaking information. :D

[SpazSinbad]

...The lost jet : https://www.navylookout.com/photo-essay-the-carrier-strike-group-the-homeward-leg/ 06 Dec 2021
"On 16th November HMS Queen Elizabeth passed through the Suez Canal and into the Mediterranean. While conducting routine flying operations on the 17th November a UK F-35 jet crashed on takeoff. Leaked footage shows the pilot ejected at the end of the ski ramp as the aircraft lacked sufficient airspeed to get airborne. Fortunately, the pilot survived and landed back on the ship under parachute and did not get wet. He has subsequently flown ashore for precautionary medical checks. Various unofficial sources report that the cause was a protective foam engine blank that was sucked into the jet, causing the loss of power. One of the blanks became dislodged and was blown out of sight into the central void in front of the engine. During pre-flight checks, the assumption was made that both covers had been removed when in fact one was lodged in the aircraft out of view. This version of events is unverified and the outcome of the investigation should be awaited before making judgements.

It has subsequently emerged that unfortunately, the aircraft lost was one of the newest in the UK fleet – ZM152. She first flew in June 2019 and would have had significantly lower Block IV upgrade requirements than older airframes. In co-operation with NATO allies, the MoD SALMO is taking the lead in the efforts to recover the wreck of the aircraft believed to be in around 1,500m of water in the Levantine Sea, South of Cyprus...."

[ORAC]

https://www.thetimes.co.uk/article/hms-queen-elizabeth-sunken-f-35-jet-is-raised-from-sea-bed-xn0dhfp9x

HMS Queen Elizabeth: Sunken F-35 jet is raised from sea bed

The wreckage of an F-35 has been recovered from the sea bed in a delicate seven-day operation involving vessels from Britain, Italy and America, as a member of the military was arrested for leaking footage about the crash….

It is understood the arrested man was a member of the crew on the aircraft carrier and has been flown back to the UK. It is unclear whether he is in the Royal Navy or RAF.….

It has taken nearly three weeks for Britain to pull together the necessary experts to lift the wreckage to the surface. Defence sources said that they were “pleasantly surprised at how quickly the recovery took”. It is understood the conditions were particularly challenging because of stormy weather.…

[T28B]

HMS Queen Elizabeth: Sunken F-35 jet is raised from sea bed
The wreckage of an F-35 has been recovered from the sea bed in a delicate seven-day operation involving vessels from Britain, Italy and America,
It is nice to have friends who can help out.
{notasamod}

[Cat Techie]

I believe it's called absolute speculation.

It is being a Licenced Aircraft Engineer that actually works with fairly modern technology. What is your knowledge of FADEC systems? Please tell me? What is a PMA? Changed the stator of one last night. What is their usual relationship with FADEC units?

[Cat Techie]

First off to your earlier query I just read, when did I last run a gas turbine, probably several months ago, when did I last run an aircraft, several this month, type ratings about 300 types and engines, also C certifying and last issuance, 3 ARCS this month as a CAMO (Nov).

As for engine indications of an imminent failure, from experience of an IGV failure on an engine reported as slow to accelerate, none or milliseconds before it all let loose and the turbine departed rearwards, First indication aircraft shaking so much you couldn’t see the instruments in front of you, followed by fire warnings, unresponsive to throttle movement and only stopped when the fuel was chopped. Every case is different.

Any update on the recovery now it’s been located?


.

300 type ratings? One only gets to be a master of a type with time on it (and read the AMM). Currency is everything as well as most people do not remember much about a type if not working on it, so you can work out my thoughts on that statement. I struggle to remember the turboprop I worked on last 4 years ago. Because I don't work on it.

Most engine blade off failures end up with the the sypmtoms you describe. Seen birdstrikes on Turbofans. Fan may survive, Stators and compresser stages behind did not.

[tartare]

An interesting little tidbit buried in the coverage:

It is understood that while the point at which the jet entered the sea is known, the aircraft’s wings would have made it glide underwater for a reasonable distance before settling on the sea bed.

[artee]

An interesting little tidbit buried in the coverage:

It is understood that while the point at which the jet entered the sea is known, the aircraft’s wings would have made it glide underwater for a reasonable distance before settling on the sea bed.

That is it's highly classified SLO (Super Low Observable) mode :E

[GeeRam]

An interesting little tidbit buried in the coverage:

It is understood that while the point at which the jet entered the sea is known, the aircraft’s wings would have made it glide underwater for a reasonable distance before settling on the sea bed.

Given it went in dirty, with the dustbin lid open and top vent doors open, and all the Dunlops dangling.....I'd be surprised if it 'glided' underwater much at all.......

[LateArmLive]

It is being a Licenced Aircraft Engineer that actually works with fairly modern technology. What is your knowledge of FADEC systems? Please tell me? What is a PMA? Changed the stator of one last night. What is their usual relationship with FADEC units?
Ooh, I do love a good quiz. I'm basing my opinion of your "absolute speculation" on actually knowing the ins and outs of the accident. You, however, have no knowledge to state there was a FADEC problem.
As for my knowledge of FADECs, it's purely from an operators experience. I think you might need to accept you know very little about the F35 engine and this accident. Maybe even stop making incredible claims, even if this is a Rumour Network.

[melmothtw]

Well, wasn't expecting this quite so soon. Good job!!

https://twitter.com/DefenceHQ/status/1468518145069625351

[Navaleye]

I wonder if any parts from that aircraft will find their way into the parts pool?

[llamaman]

I wonder if any parts from that aircraft will find their way into the parts pool?
There's half a pair of intake blanks available.

[SATCOS WHIPPING BOY]

Given it went in dirty, with the dustbin lid open and top vent doors open, and all the Dunlops dangling.....I'd be surprised if it 'glided' underwater much at all.......
Ah, but it did have the additional buoyancy aid which, by my very detailed calculations based purely on rumour, speculation and reliable leaked sources, would have extended it's glide range by 300.164 metres (+/- 300metres )

;-)

[Chugalug2]

From the Daily Telegraph today :-
The RAF F-35 jet recovered from the Mediterranean seabed was found shattered into multiple pieces.

The stealth fighter that crashed during an attempted take-off from HMS Queen Elizabeth last month (https://www.telegraph.co.uk/news/2021/11/17/raf-jet-crashes-sea-pilot-ejects-mediterranean/) was recovered after a multinational operation involving US and Italian forces.

A spokesman for the MoD said the wreckage had broken into multiple pieces and was found in “significant large parts”.

All sensitive equipment and aircraft parts had been secured, the spokesman confirmed.

The loss of the jet in the Mediterranean Sea prompted a desperate three-week search to ensure sensitive technology did not fall into Russian hands. (https://www.telegraph.co.uk/news/2021/11/19/russia-paying-close-attention-hms-queen-elizabeth-race-salvage/)

A member of the crew, arrested in relation to the unauthorised release of footage of the crash, has been flown back to the UK.

An MoD spokesman said Royal Navy warships worked with the Italian Navy and US and Italian salvage vessels to retrieve the jet.

RAF personnel embarked on the salvage vessels throughout the recovery operation.

The Telegraph understands the Defence Safety Authority has convened an investigation and will determine where the aircraft wreckage will be taken.

Given the force of impact as the jet toppled off the front of HMS Queen Elizabeth, it is likely the lift-fan door, open on take-off to provide downward thrust, would have broken away when the aircraft hit the water.

The wheels and landing gear bay doors, which would also have been open for the launch, could also have snapped off.
Cause of the crash still to be determinedThe £100 million jet crashed last month during a routine flight. The cause of the crash has yet to be determined but it is thought a plastic covering (https://www.telegraph.co.uk/news/2021/11/24/raf-f-35-jet-crashed-sea-plastic-rain-cover-left/), designed to keep debris out of the engine intake vents, had been left on the jet and ingested by the aircraft causing the engines to fail.

Justin Bronk, of the Royal United Services Institute, said the fact the crashed aircraft was one of the newer F-35Bs in the UK fleet, meant it was a “greater loss”.

The numerous technical elements of the F-35 programme have developed at differing rates, meaning the older jets have already been overtaken in some areas by newer airframes and need to be updated.

The crashed aircraft, tail number ZM152, first flew in June 2019 and therefore had “significantly lower” upgrade requirements than the older jets in the fleet.

Mr Bronk said: “The cost to make existing F-35 airframes fully Block IV capable (more power, cooling, processing power, some upgraded sensors etc) is higher the older an airframe is because the really early production airframes need a lot of internal work compared to newer ones.”

An MoD spokesman said: “Operations to recover the UK F-35 in the Mediterranean Sea have successfully concluded.

“We extend our thanks to our NATO allies Italy and the United States of America for their support during the recovery operation.”


https://www.telegraph.co.uk/news/2021/12/08/wreckage-raf-jet-crashed-mediterranean-found-shattered-pieces/

[Willard Whyte]

The principal question is whether the damage will buff out.

[ZH875]

The principal question is whether the damage will buff out.
Will Speed Tape and Black Bodge Tape stick to a soggy airframe?

[ancientaviator62]

I wonder what they will charge the 'arrested crew member' with ?

[Ninthace]

Now that the offending ac has been fished out of the oggin, should the title of this thread be changed, as ‘tis no longer lost?

[alfred_the_great]

I wonder what they will charge the 'arrested crew member' with ?

id imagine misconduct, or some such, probably based on mobile phone in a compartment which shouldn’t have them. Admin warnings as well.

[Bengo]

I wonder what they will charge the 'arrested crew member' with ?
You can always start with "Conduct prejudicial"😊
N

[ancientaviator62]

Ah the infamous 'conduct prejudicial' the last resort catchall of the military legal system. I would have thought it had been removed from the list in this day and age.

[Navaleye]

Strange how whistle blowers are praised as heroes in the media for exposing what would otherwise be covered up. In the military however it is akin to treachery demanding the strongest punishment possible sanctions.

[212man]

Given the force of impact as the jet toppled off the front of HMS Queen Elizabeth, it is likely the lift-fan door, open on take-off to provide downward thrust, would have broken away when the aircraft hit the water.

The wheels and landing gear bay doors, which would also have been open for the launch, could also have snapped off.

Not to mention hitting the ground after falling for a mile! People underestimate the speed of sinking objects.

[ORAC]

Let alone being run over by a 65,000 ton aircraft carrier if it didn’t sink immediately.

One of the disadvantages of not having an angled deck…..

[SATCOS WHIPPING BOY]

Not to mention hitting the ground after falling for a mile! People underestimate the speed of sinking objects.
or having a 65,000 tonne carrier rear-end you at 20+ knots.

ORAC SNAP , LOL.

[ACW599]

Will Speed Tape and Black Bodge Tape stick to a soggy airframe?

Bodge tape is so last year. Araldite and Jo-bolts are the modern way.

[NutLoose]

I wonder how fast it sank and did the ship hit it on its way over it.

[Krystal n chips]

Bodge tape is so last year. Araldite and Jo-bolts are the modern way.

Perhaps not a good idea to suggest Jo-Bolts given the unfortunate use of a signature to authorise robbery of such from one F-4 to another at Bruggen

[Gordon Brown]

Strange how whistle blowers are praised as heroes in the media for exposing what would otherwise be covered up. In the military however it is akin to treachery demanding the strongest punishment possible sanctions.

How was it whistleblowing? What evidence is there that the F-35 was engaged in unlawful activity? I would imagine that the rules on PEDs in such environments were pretty clear, so perhaps less whistleblowing, more basic disobeying the rules.

[Auxtank]

QE due alongside Pompey this afternoon.
Looks like the absence of one jet has given her a pronounced list to starboard . . .

https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/505x644/qelist_7bbfc9747171712383aa353d736fa253c7039296.png
https://www.bbc.co.uk/news/uk-england-hampshire-59593047

[dctyke]

Do the navy still have shore leave after deployments at sea and do RAF personnel enjoy the same treatment?

[Auxtank]

Do the navy still have shore leave after deployments at sea and do RAF personnel enjoy the same treatment?

Certainly the RN personnel - they'll be off for X-mas now. Not sure about RAF.

[Timelord]

Certainly the RN personnel - they'll be off for X-mas now. Not sure about RAF.

They’ll be off to Prince of Wales

[Video Mixdown]

With the SHAR, by the time you noticed something was wrong you were going off the end - one way or another. Just no time (or brakes) to stop.

Mog
Was there ever a time when an aircraft, having started it's take-off run from a carrier had the time or room to stop? Hundreds of aircraft must have been lost like that over the years, with many fatalities.
​

[Mogwi]

Yes, I guess the last time that it was possible was pre-catapult, when it was possible to check full power on the brakes before committing. You still had to judge the deck pitch though and could end up with a face-full of oggin if you timed it wrong. One advantage of the ramp!

Mog

[Warren Peace]

I suspect that some of it buys great big houses in Lancashire.


I am outraged by this.

Seriously? The Sun posts it - Twatter follows it up - all based on (probably) THIS Forum and egoat.

Are you seriously saying that EICAS wouldn't have picked this up at Idle Power?

Even though it'll report the fact that you've left the port side ashtray lid open.

If so, I'm confused as to what the $100M price tag is paying for.

[Auxtank]

I suspect that some of it buys great big houses in Lancashire.

Yeeees.
Hope now everyone's ashore getting wrecked in Pompey it's not a case of "Here endeth the lesson."

Somebody on this thread stated that $100M constituted 3 days expenditure by the NHS.
"Puts it in to perspective. Too much bloody perspective if you ask me." (Spinal Tap, MOVIE Quote)

https://www.youtube.com/watch?v=nAruBWa7LGk

[Fonsini]

Did I miss the recovery? Any photos ??

[Auxtank]

No photos. No details.
As expected and one must therefore assume a successful recovery of all the important bits - which is basically all of it.
The Ejector Seat will be missing - which is good.

https://www.thedrive.com/the-war-zone/43423/the-wreck-of-a-crashed-british-f-35-has-been-pulled-out-of-the-mediterranean

[Bing]

Yeeees.
Hope now everyone's ashore getting wrecked in Pompey it's not a case of "Here endeth the lesson."

Somebody on this thread stated that $100M constituted 3 days expenditure by the NHS.
"Puts it in to perspective. Too much bloody perspective if you ask me." (Spinal Tap, MOVIE Quote)

https://www.youtube.com/watch?v=nAruBWa7LGk

It's about six hours expenditure by the NHS, or as someone else put it 'barely gets you to an early breakfast on new year's day'. NHS budget is £150B so ~£400m a day.

[alfred_the_great]

Do the navy still have shore leave after deployments at sea and do RAF personnel enjoy the same treatment?

You’d hope the RAF has learned about this post-PITTING…

[Cat Techie]

Ooh, I do love a good quiz. I'm basing my opinion of your "absolute speculation" on actually knowing the ins and outs of the accident. You, however, have no knowledge to state there was a FADEC problem.
As for my knowledge of FADECs, it's purely from an operators experience. I think you might need to accept you know very little about the F35 engine and this accident. Maybe even stop making incredible claims, even if this is a Rumour Network.

Most people on here flew gas turbines with HMUs with no high end IEC protection or FADEC. Did you? I am not 60 years old yet. Operators are not engineers. When it goes wrong, do you have a clue? No. You put Inop in the tech log / F707A and expect me to work out the snag with mimimal info.. ;) The F135 engiine on this F35B sucked a major FOD item into its P2 point at an entry speed of 0.5 Mach. Basic gas turbine theory taught in the RAF and module 15 of the B1 theory exams. Expect carnage. 300 type courses mean nothing if you cannot remember the basics. So end the lesson.

[LateArmLive]

Most people on here flew gas turbines with HMUs with no high end IEC protection or FADEC. Did you? I am not 60 years old yet. Operators are not engineers. When it goes wrong, do you have a clue? No. You put Inop in the tech log / F707A and expect me to work out the snag with mimimal info.. ;) The F135 engiine on this F35B sucked a major FOD item into its P2 point at an entry speed of 0.5 Mach. Basic gas turbine theory taught in the RAF and module 15 of the B1 theory exams. Expect carnage. 300 type courses mean nothing if you cannot remember the basics. So end the lesson.
I don't really care how old you are, but thanks for the story. As for your theory above - where does the "FADEC problem" you previously claimed come into things?

[Buster15]

I don't really care how old you are, but thanks for the story. As for your theory above - where does the "FADEC problem" you previously claimed come into things?

Two completely separate things.
FADEC Engine control simply takes on some of the engine management and handling requirements and does them a bit more accurately.
But, however the engine is being controlled, severe FOD will result in a significant reduction in engine thrust, sometimes with engine surge which may become locked in.

[NutLoose]

Most people on here flew gas turbines with HMUs with no high end IEC protection or FADEC. Did you? I am not 60 years old yet. Operators are not engineers. When it goes wrong, do you have a clue? No. You put Inop in the tech log / F707A and expect me to work out the snag with mimimal info.. ;) The F135 engiine on this F35B sucked a major FOD item into its P2 point at an entry speed of 0.5 Mach. Basic gas turbine theory taught in the RAF and module 15 of the B1 theory exams. Expect carnage. 300 type courses mean nothing if you cannot remember the basics. So end the lesson.

Err why are you having a pop at me? and quoting someone else? Perhaps one needs glasses. I wasn't the one asking the question. I would point out though FADEC is on everything these days, not just turbines.
And for your info as you appear to be having an unwarranted pop at me, I was an A Tech P in the RAF and post RAF have worked on Learjets, Beechjets, Citations, Gulfstreams, Falcons and turboprops galore.


..

[Imagegear]

For those who may not have seen it....flopping off the ramp at the 7:10 point:

F35B Ramp Flop

IG

[NutLoose]

At 3.02 if only she knew ;)

[Buster15]

Err why are you having a pop at me? and quoting someone else? Perhaps one needs glasses. I wasn't the one asking the question. I would point out though FADEC is on everything these days, not just turbines.
And for your info as you appear to be having an unwarranted pop at me, I was an A Tech P in the RAF and post RAF have worked on Learjets, Beechjets, Citations, Gulfstreams, Falcons and turboprops galore.


..

Well said.
I don't understand why the subject of FADEC is being referred to in this instance.
But to clarify.
A GT engine may feature either Inlet Guide Vanes at the front of a compressor or Variable Guide Vanes or Bleed/Blow Off Valve at the rear of the compressor.
Both of these features would be controlled by the FADEC.
However, these are specifically to act as airflow aerodynamic devices to either raise the surge line or reduce the compressor running line.
But they would not be able to cope with compressor mechanical damage resulting in a surge.
On a typical modern GT, with a pressure ratio of over 25/1, a surge would happen incredibly quickly.
Certainly significantly faster than the normal FADEC data refresh rate of around 5 to 10Hz. And there is then the matter of the IGV/VGV/BV response time.
This would be nothing like fast enough to get anywhere near able to react to a compressor mechanical damage caused surge. And should the damage become serious enough, the surge would lock in meaning that the engine would have be either throttled back or more likely shut down.

[melmothtw]

No photos. No details.

Indeed, you have to suppose that there's a reasonable chance they (or another maritime F-35 operator) may have to do this again over the course of the jet's lifespan, and don't want to give too much away as to how they managed it this time around.

[gums]

Salute!

Good poop, Buster. Thanks.

Only bad FOD I ever had was a chunk of ice that had built up in the intake and the end-of-rwy troops didn't see it. Ingested just after gear came up. Being a P&W F100 turbofan the chunk was diced and sliced, then mostly went thru the bypass ducting. Was in a Viper, so sucker struck the fan blades right under my seat, so it was very apparent something was awry. Secondly, when I retarded throttle I "felt" a vibration, so came back pronto for a heavyweight landing without touching the throttle again until rolling out. Had about 60 to 70 big compressor blades on first two stages missing chunks or severely bent. I don't know how much the damage reduced my power, but I had "enough" and did not tempt fate.

Can't imagine getting the F-35B off the deck without max specified power and some wind over the deck. And BTW, seems the USN did a "cold cat" test for their Cee model. Prolly find something over on the F-16 dot net F-35 forums.

Gums sends...

[melmothtw]

Can't imagine getting the F-35B off the deck without max specified power and some wind over the deck.

Well, they did launch one while the ship was stationary in Portsmouth some months back so doesn't necessarily need wind over the deck. Of course, no idea who much fuel etc that was carrying, but the MoD did say that this crashed aircraft was not carrying any stores so wouldn't have been that heavy.

[Buster15]

Salute!

Good poop, Buster. Thanks.

Only bad FOD I ever had was a chunk of ice that had built up in the intake and the end-of-rwy troops didn't see it. Ingested just after gear came up. Being a P&W F100 turbofan the chunk was diced and sliced, then mostly went thru the bypass ducting. Was in a Viper, so sucker struck the fan blades right under my seat, so it was very apparent something was awry. Secondly, when I retarded throttle I "felt" a vibration, so came back pronto for a heavyweight landing without touching the throttle again until rolling out. Had about 60 to 70 big compressor blades on first two stages missing chunks or severely bent. I don't know how much the damage reduced my power, but I had "enough" and did not tempt fate.

Can't imagine getting the F-35B off the deck without max specified power and some wind over the deck. And BTW, seems the USN did a "cold cat" test for their Cee model. Prolly find something over on the F-16 dot net F-35 forums.

Gums sends...

Sounds like good airmanship on your behalf.
I guess that you were in reheat on t/o and then cancelled reheat.
The F100 is a pretty sturdy engine.
I was used to working on military twin engine jets. For example, on Tornado, the FRC's said something like - in the event of an engine mechanical failure on take off, leave the engine throttle at its power setting and climb to safe height. Then throttle back to a safe setting and land as soon as possible.
Much like the F100, the RB199 was a (high) bypass engine and was pretty good at sending FOD down the bypass duct.
But hard body FOD did sometimes go into the small IP and even smaller HP compressor. And then you were in trouble.
NB. Never a pilot. Only an engineer by the way.

[gums]

Salute!

Yeah, Buster, many of we colonists liked the Pratt motors as they were "robust". OTOH, the GE and Rolls motors were very high performance and lighter ( more thrust per pound). So I had a thousand hours in the Allison /Rolls fan in the A-7D with no problems, Great fuel consumption and so forth.

Best example of the fan bypass in the TF-41/Spey motor was ingestion of a flock of seagulls at Myrtle Beach. Motor coughed, belched and lost power. Pilot turned back and landed opposite rwy to show us the roasted birds!! Some were impaled on the bomb racks, but a few were lodged in the bypass duct. Suckers were toasty!

Gums recalls....

[Timelord]

Not to quibble, but for the record: The Tornado drill for an engine failure on take off after decision speed was:

Throttles (note the plural) …..Combat
Landing gear…………………..Up
External load…………………..Jettison if necessary

And once at a safe height and speed shut down the affected engine.

NB Never a pilot or an engineer, only a navigator.

[tdracer]

On a typical modern GT, with a pressure ratio of over 25/1, a surge would happen incredibly quickly.
Certainly significantly faster than the normal FADEC data refresh rate of around 5 to 10Hz. And there is then the matter of the IGV/VGV/BV response time.


Some thread drift here, but having worked modern FADECs, that's not entirely true. Modern FADECs have surge detection/recovery logic that was completely lacking in the older hydro controls, so surges can be dealt with far more effectively. Further, the update rate varies dramatically depending on the particular FADEC function. We break the FADEC down into 'major frame' and 'minor frame'. Major frame means the FADEC has done pretty much everything it can do every major frame (there are sometimes a few engine monitoring functions that don't happen every major frame, but they are strictly things that don't in any way actually affect the actual engine control). Major frame update rates are typically around 200 milliseconds (e.g. 5 Hz). The more time sensitive tasks are done up to once per 'minor frame'. Depending on the task, it may happen once per minor frame, once every two or four minor frames, all the way up to once per major frame. For example, the fuel metering valve position command is updated every minor frame. Not familiar with the newest crop of Pratt FADECs, but on the modern GE FADECs the minor frame is 15 milliseconds (~66 Hz).

In short, modern FADECs can deal much faster and more effectively with a surge. However if the surge was caused by mechanic damage (e.g. FOD) - rather than a temporary airflow disruption, it may not matter.

[tdracer]

Salute!

Yeah, Buster, many of we colonists liked the Pratt motors as they were "robust". OTOH, the GE and Rolls motors were very high performance and lighter ( more thrust per pound). So I had a thousand hours in the Allison /Rolls fan in the A-7D with no problems, Great fuel consumption and so forth.

Best example of the fan bypass in the TF-41/Spey motor was ingestion of a flock of seagulls at Myrtle Beach. Motor coughed, belched and lost power. Pilot turned back and landed opposite rwy to show us the roasted birds!! Some were impaled on the bomb racks, but a few were lodged in the bypass duct. Suckers were toasty!

Gums recalls....
Yea Gums, back in the day the saying (at least on the commercial side) was that Pratt engines surged easily, and could happily surge all day long without doing any real damage. GE engines hardly ever surged, but if it did it was a light bulb - you removed and threw it away and installed a new one.
However, around 1990 that sort of changed - the new Pratt engines still surged on a regular basis, but now the surge might well break them, while GE engines still seldom surged, but if they did it usually didn't hurt them. It took until the early 2000's for Pratt to come out with a fix for the surge problems with the PW4000 - and it involved a complete redesign of the HP compressor (and a very expensive mandatory retrofit to a fleet of several thousand engines).

[Buster15]

Not to quibble, but for the record: The Tornado drill for an engine failure on take off after decision speed was:

Throttles (note the plural) …..Combat
Landing gear…………………..Up
External load…………………..Jettison if necessary

And once at a safe height and speed shut down the affected engine.

NB Never a pilot or an engineer, only a navigator.

Quite correct. I was of the assumption that take off was at Max reheat. So you are right about going into combat.
Being a navigator certainly trumps an engineer by a big margin.

[Buster15]

Some thread drift here, but having worked modern FADECs, that's not entirely true. Modern FADECs have surge detection/recovery logic that was completely lacking in the older hydro controls, so surges can be dealt with far more effectively. Further, the update rate varies dramatically depending on the particular FADEC function. We break the FADEC down into 'major frame' and 'minor frame'. Major frame means the FADEC has done pretty much everything it can do every major frame (there are sometimes a few engine monitoring functions that don't happen every major frame, but they are strictly things that don't in any way actually affect the actual engine control). Major frame update rates are typically around 200 milliseconds (e.g. 5 Hz). The more time sensitive tasks are done up to once per 'minor frame'. Depending on the task, it may happen once per minor frame, once every two or four minor frames, all the way up to once per major frame. For example, the fuel metering valve position command is updated every minor frame. Not familiar with the newest crop of Pratt FADECs, but on the modern GE FADECs the minor frame is 15 milliseconds (~66 Hz).

In short, modern FADECs can deal much faster and more effectively with a surge. However if the surge was caused by mechanic damage (e.g. FOD) - rather than a temporary airflow disruption, it may not matter.

Appreciate that. Thank you.

[SATCOS WHIPPING BOY]

Quick (off topic question), is this what a surge would look like? F-18 departing Leeming yesterday afternoon. Returned shortly thereafter having dumped fuel and prepped for a cable engagement which was not needed in the end.

https://cimg5.ibsrv.net/gimg/pprune.org-vbulletin/1937x810/f18_1_fa2d6ea841730e75b5a9b31acb2662ddd8d4784b.jpg
https://cimg6.ibsrv.net/gimg/pprune.org-vbulletin/1692x605/f18_2_50f8b9a10f47c7b331a804dc50a5ffe98dfe80da.jpg

[SpazSinbad]

F-18C Engine Surge Series: https://i1.wp.com/theaviationist.com/wp-content/uploads/2009/10/sequenza-sfondo-bianco_lr.jpg

ZOOM: https://i2.wp.com/theaviationist.com/wp-content/uploads/2011/08/Compressor-surge.jpg

TEXT: https://theaviationist.com/2011/08/22/flameout/
https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1496x298/f_18chornetcatenginesurgeseries2009aviationist_900666db342be 775eedba956076abf4bdbe40378.jpg

[SATCOS WHIPPING BOY]

Thank you SpazSinbad. Much appreciated, looks exactly like what was seen. :ok:

[averow]

I had not considered that consequence after an incident on the ramp or with a catapult ! So a pilot might be launched a few degrees port of the the axis of the ships motion for precisely this reason?

[gums]

Salute!

averow
Not being a nasal radiator, but talking and working with some.....
The deal is wind over the deck, and the path of the boat does not have to be aligned as you may think. So the angled deck is a good thing if you have a cold cat or motor problem on the roll. Have to get a true nasal radiator to confirm.

Gums sends...

[SpazSinbad]

The CVN 'steams' along a steady course into wind, creating WOD Wind Over the Deck. One may see the four catapults are not exactly aligned along the 'steaming path', so there is usually a slight crosswind component during catapulting. The maximum crosswind is determined for each aircraft during initial testing ashore (when wind more or less in correct direction for the test) then on a carrier(s) before that aircraft becomes qualified to operate from a carrier. For example the F-35C had a lot of tests for CVN carrier qualification as well as the F-35B for various decks.
Flight Operations | The Skyhawk Association (https://skyhawk.org/page/flight-operations) & https://skyhawk.org/sites/default/files/images-units-ships/cv-flight-deck-layout.jpg
For the F-35B it is easier for the ship axis to be aligned to STO path however it may not always be exact - one would have to see overhead photos and the take off path etc for each F-35B flat/ski jump deck. On a CVN the landing path (angle deck) is 9 degrees so an approaching aircraft is always nibbling left/right to correct for the centreline which is always moving from left to right during the approach. Again there is a crosswind limit for each aircraft type then limits for weather generally and perhaps pilot skill or the LSO just has had enough. :-)
https://cimg0.ibsrv.net/gimg/pprune.org-vbulletin/960x240/cv_flight_deck_layout_38ac4865f5043002bef0b88bcc6941dff4b0fd 11.jpg

[langleybaston]

Not forgetting that "wind direction and speed" is a concept, rather than a fact. Look at an anemograph trace on a lively day..

Met. will report xx knots, gusts yy/, direction zzz, but apart from yy these are averages over a long period compared with the length of time to launch, be it CAT, ramp or anything fancy. After decision time nobody on God's earth knows the parameters in the next couple of seconds. The only controllable is ship's course, which might be a judgement call or might be dictated by the tactical situation.

Or, from a Metman's point of view, the pilot/ crew have my utmost admiration.

As an aside, I served at two stations where wind reversal was fairly common and UNPREDICTABLE except in the sense that we knew that it might happen, but not when.
Leeming and Nicosia. Fortunately OC OPS/ Flying and the Duty Pilot knew enough to know there were known unknowns.

[FlightDetent]

I heard once from a sailor that, unlike for landbound aviation, their wind is steady?

Lack of orography, it's purely the pressure gradients making things happen. Save for the turbulent layer with limited thickness.

[SpazSinbad]

The CVN wind system MORIAH (they call the wind mariah) is described along with accuracy concerns etc in the six page PDF attached.

STRIKE TEST NEWS Air Test and Evaluation Squadron 23 Newsletter 2013 LCDR Pat “WHO?” Bookey
"...The wind over the deck (WOD) is measured from three anemometers on the ship (FWD, STBD, and PORT). These three anemometers feed the Moriah System, which is the wind display in PriFly and the bridge that is used to drive the ship to get recovery WOD. The Moriah display from the Mini Boss station allows the different anemometers to be selected individually. The FWD anemometer is at the top of the navigation pole to the right of catapult #1. The PORT and STBD anemometers are at the top of the mast on the island on outriggers on the port and starboard sides...." http://www.navair.navy.mil/nawcad/index.cfm?fuseaction=home.download&id=767

https://cimg8.ibsrv.net/gimg/pprune.org-vbulletin/1680x1050/moriahcvndisplay_28cf6a965d866c9a7978e77b4fe1f15e9f7c896e.jp g

[Asturias56]

Given the habit of politicians rushing to make (often nonsensical) speeches about all things Defence in the UK I wonder who will draw the short straw to have to announce why the aircraft as lost..... or will it be buried for 18 months before slipping out in a report on Christmas Eve?

[GemDeveloper]

I have only just hoisted in that the embarked Squadron was 617.

Any truth in the rumour that their motto is being changed to Avec moi le déluge?

[langleybaston]

I heard once from a sailor that, unlike for landbound aviation, their wind is steady?

Lack of orography, it's purely the pressure gradients making things happen. Save for the turbulent layer with limited thickness.

Beg to differ. That is not the whole truth. How does that generalisation explain "cats paws" caused by down gusts on calm open waters? In any case lack of obstruction is not confined to open water. One of my tasks was trying to optimise anemometer siting on RAF airfields, subject to ATC and OPS constraints. Unsurprisingly a lot of airfields are very flat with minimal obstruction, and we tried to put the anemo where the gust ratios were least. Partly because the wind has a non-zero vertical vector there is no escaping gustiness in winds of any consequence. Sods Law says that the anemo ends up in a less than ideal place for aircraft landings/ take-offs.

Gust-ratio is a different matter: the more built-up the airfield is, the higher the ratio of gust to average wind. Can exceed 2 : 1 in cities. That does not extrapolate downwards all the way to a 1 : 1 ratio at sea.

As to whether this really matters is an airmanship subject, and the biggest thing I have ever flown is a boomerang, so am not qualified.

[FlightDetent]

Thanks for confirming my suspicion, stemming from the debate observed above.

[SpazSinbad]

Measuring the wind & WOD is fraught for sure. Allowances +/- are made for the uncertainty of it all. Recall that a ship at sea has Six Degrees of Freedom to confound the wind. The USN LSOs have muchos gadgets to measure all kinds of things during an aircraft approach. The CAT/Launch officer relies on the measures taken - displayed elsewhere - then a traffic light and his/her own judgement about those 6 degrees of freedom before signaling GO. The USN has undertaken lots of studies to measure and mitigate the BURBLE caused by the Island at various spots behind a CVN for approaching aircraft. The FORD class has extra measures to reduce/mitigate this effect (smaller island further aft with fillets on back end of the deck. The Brits invented the 'hurricane bow' to increase the safety for aircraft Ops, whilst of course later inventing the ski jump to increase STO launch safety amongst other effects for suitable aircraft.

During the Sea Venom era particularly, HMAS Melbourne would chase the wind lanes in an otherwise calm South China Sea on hot days to be able to launch those aircraft with transverse (fore & aft) G-limited airframes. The A4G could be launched at 9G transverse limit with usually the 5-6G experienced good enough. It was not unusual to see the tops of the long Pacific swell swirling down the 100 foot catapult track, so timing the launch could be vital. I have been told that my wheels creased the water as I climbed away but I have no recollection of this happening nor could I see this myself anyway, I have other memories. :-)

Ship 6 Degrees of Freedom:
The ship rotational degrees of freedom are termed roll, pitch, & yaw. In the translational degrees of freedom, up and down motion is called heave, forward to aft motion is called surge, & port to stbd motion is called sway.”

https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1601x1050/6degreesfreedomcvn_eeb8be2ee06c020d7a2be01440eb89a094c174c3. jpg

[MightyGem]

I heard once from a sailor that, unlike for landbound aviation, their wind is steady?
.

I think that that's probably more a reference to the wind over the deck caused by the ship doing 30kts.

[pasta]

I think that that's probably more a reference to the wind over the deck caused by the ship doing 30kts.
The wind experienced in a sailing boat is a lot more constant away from the effects of land, though it's obviously not uniform. There also tends to be quite a bit less diurnal variation; the wind at sea doesn't drop at night to the same degree it generally does on land.

[langleybaston]

Correct. Text book.

[gums]

Salute!

I always thot the nasal radiators used a flare on the bow and then turned the boat until the smoke went down the deck. And that would seem to work even with the angled deck. Although I unnerstan that landing would involve some different geometry and flight path, but not as much as 20 knot croswind on a land runway.

Gums wonders....

[SpazSinbad]

The PDF shows the instruments (also photo) seen by CVN crew to get WOD. The USN CVN crowd are able to carry out simultaneous cats & arrests (me old MELBOURNE could not do this) so there is a compromise for WOD. LAUNCH & RECOVERY BULLETINS for each aircraft state limits for operations of that aircraft. The CVN will work within those parameters when possible. I suppose in really awkward conditions they may not operate launch/land together. The flight deck of a CVN is a busy place indeed. The deck height is about 67 feet with anenanenanennommetters recording wind speed as stated so the readings are as accurate as possible. LSOs have a swathe of instrumentation to goggle at with main LSO concentrating on approaching aircraft so 'the LSOs' know when conditions are not within limits in real time. "POWER POWER POWER don't CLIMB". The flare (fired into the air from port side out to port) was used by the 'NON-LSO' in the Sea Venom era aboard MELBOURNE to wave off aircraft when I guess the deck was foul. During that era MELBOURNE did not have LSOs. Using a flare on deck probably not a good idea due fire hazard etc. Never heard of it meself.

[Bing]

Using a flare on deck probably not a good idea due fire hazard etc. Never heard of it meself.

WW2 era British carriers had a steam feed to the bow which could be used to give a relative wind direction indication. Some pictures show calibrated markings around it to give the angle. Probably made redundant by the steam catapult doing the same thing as a side line.

[SpazSinbad]

Looks like EAGLE had the same problem as MELBOURNE with the catapult start in the landing area. We see a Buccaneer being launched after the post 1964 refit: https://i.redd.it/sa5vv5prv5s31.jpg I'll guess we can see a wisp of steam in middle of bow? Or something else? HMS Eagle R 05 Audacious class aircraft carrier Royal Navy (seaforces.org) (https://www.seaforces.org/marint/Royal-Navy/Aircraft-Carrier/R-05-HMS-Eagle.htm) and HMS Theseus bow markings: https://www.seaforces.org/marint/Royal-Navy/Aircraft-Carrier/Colossus-class_DAT/R64-HMS-Theseus-03.jpg (ZOOM)

https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1654x1019/eaglecatbuccaneer1964postrefit_69b74cdd7e91b68df25bca2d3fe97 1d42761c029.jpg
https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/1654x1022/hmstheseusr64bowzoommarkings_b36f184c88bfdf2317f10f24920960f f499c4802.jpg

[NutLoose]

https://i.imgur.com/aXBYEqq.gif

[SpazSinbad]

:} Forgot to check the WOD? I like the way he gets back on his feet. COOL BEANS. :E

[megan]

Better than the alternative Nutty, he did survive though.

https://www.youtube.com/watch?v=XC1TCXyCqrg

[Solar]

Obviously not a professional footballer.

[YRP]

Ship 6 Degrees of Freedom:
The ship rotational degrees of freedom are termed roll, pitch, & yaw. In the translational degrees of freedom, up and down motion is called heave, forward to aft motion is called surge, & port to stbd motion is called sway.”


Is this not overcomplicating things? Would it not be easier if they just held the ship steady, no? :}

(Some great reading on this thread, thanks for all the good posts).

[NutLoose]

This is pitch

https://youtu.be/L4D6GxkPMgs

[SpazSinbad]

Is this not overcomplicating things? Would it not be easier if they just held the ship steady, no? :}
(Some great reading on this thread, thanks for all the good posts).
Some more great reading about Naval Aviation may be found here: https://www.faaaa.asn.au/our-history/spazsinbad-a4g/
:E Not only are there 6 degrees of freedom but also 'urinating into the WOD' is verboten. :eek:

[tartare]

This is pitch

https://youtu.be/L4D6GxkPMgs

That's staggering - amazing they kept flying - although I suppose it's simply a denser fluid...

[SpazSinbad]

That's staggering - amazing they kept flying - although I suppose it's simply a denser fluid...
Some photos/videos can be deceptive depending on factors such as viewing angle while without context lots can be surmised that is not true. The S-2 is flying into SEASPRAY, recall the flight deck in this instance is probably some fifty feet ASL. Sure WX is rough while perhaps the launch is mistimed however the aircraft is not disappearing into a wave but the spray from the wave below it. Nevertheless it is a spectacular video. It is a free deck take off in a storm, with the story on the internet and probably in my big PDF - I'll look.

Story here is just INaccurate: The Time a Plane Launched Directly Into a Wave (popularmechanics.com) (https://www.popularmechanics.com/military/aviation/a14382280/the-heart-stopping-moment-a-carrier-airplane-flies-through-a-wave/)

S-2 Tracker Free Take Off into a Wave Spray High WOD Heroes

https://www.youtube.com/watch?v=X4-qYKiHL-I

[SpazSinbad]

"...The bulk of the [Japanese F-35A] aircraft’s wreckage remains on the sea-floor, approximately 5,000 feet underwater. Although it was previously reported by local media that an extensive underwater search recovered the aircraft’s flight recorder, it was too badly damaged (crashed at an [estimated speed of 690 MPH]) for any data of the flight to be retrieved...." https://www.defensenews.com/global/asia-pacific/2019/06/10/japan-blames-spatial-disorientation-for-f-35-crash/

[langleybaston]

Some more great reading about Naval Aviation may be found here: https://www.faaaa.asn.au/our-history/spazsinbad-a4g/
:E Not only are there 6 degrees of freedom but also 'urinating into the WOD' is verboten. :eek:
And honking up is worse. I once witnessed it on a ferry to Guernsey, and the poor sod lost his upper set in the process. They ended up 6 feet behind him.
Yurrrrgh.

[SpazSinbad]

An example of the 'wind measuring devices' anneenenoonenomomeeters for the F-35B tests aboard CAVOUR. 6 page PDF attached.
...NAWCAD Prepares for Sea Trials By Bob Kaper... [Naval Air Warfare Center Aircraft Division]
...The first simulation session was takeoff and landing training for the ITF test pilots. “We created every sort of testing point such as taking off with different weight, center of gravity, weapons load, asymmetrical loading and wind angle and speed,” said Robert Parlett, F-35 simulation engineer/operator.

The simulator also created replicas of the forces acting on the virtual aircraft along with data from virtual measuring instruments installed on it. As an example, the upward curvature of the ramp produces more force on the nose landing gear than the main landing gear, creating an upward pitching force.

The second phase of the simulator training involved the landing signal officer and air boss in the flight control station. The third simulation phase was training for Cavour crew members.

“Cadence includes how they say things, but also the pace and phrasing,” he said. “The timing between ‘ready’ and ‘clear for takeoff’ on an airfield and on the ship can be totally different because it may take much longer to get ready on the ship.”...

...ATR’s [Atlantic Test Ranges] optical team meanwhile tracked the aircraft through video cameras placed around the ship and monitored wind conditions. To check for clean air behind the bow wake, the team installed two 38-foot-high, pole-mounted anemometers on deck—one at the bow and one at the stern. [SOME NUMNUTS at this time on the internet characterised these towers as LIGHTNING RODS!] They also placed a laser-based anemometer called a lidar at the bow to measure winds at 65 feet. [THIS ONE PARTICULARLY] “All in all, it was a pretty good team effort,” Combs said. “We got an ‘attaboy’ from the ITF. They said ‘best TM (telemetry) on a ship yet’.”
— Bob Kaper is a senior technical writer for Atlantic Ranges & Targets. https://www.navair.navy.mil/sites/g/files/jejdrs536/files/document/%5Bfilename%5D/NAN%20Spring2021_web.pdf (5Mb)

[SpazSinbad]

In my research often USN NATOPS do not describe Carrier Approach Technique and may refer to a cryptic FCLP technique elsewhere. Recently I came across this short description below which may answer a few previous questions. I forgot about NIL Wind with the carrier having to make WOD issues.

NATOPS FLIGHT MANUAL 15 April 1968 Navy Model F-8A, F-8B AIRCRAFT
CARRIER-BASED PROCEDURES - CARRIER LANDING

"Refer to field carrier landing practice, this section, for additional information, to figure 3-11 for illustration of a typical carrier landing, and to section I, part 4 for carrier operating limitations. [Later I may excerpt the FCLP text]

While maneuvering to enter the traffic pattern, attempt to determine the sea state. [I believe these days the USN LSO gives this info or is given during marshal] This information will be of value in predicting problems that may be encountered during the ensuing approach and landing.

If the sea state is smooth, the carrier is creating all (or most) of the wind over the deck by hard steaming. Avoid entering the pattern at gross weights near the maximum since the approach speed could exceed the maximum engaging speed. Expect the wind to be down the axial deck which will result in a 10° crosswind when lined up with the angled deck. Stack wash will be encountered, so expect some turbulence when approaching the ship's wake. Pay particular attention to lineup.

With a moderate sea state, the carrier should be able to place the wind down the angled deck so lineup will not be a problem. As the wind over deck increases, additional power will be required to fly a proper approach.

If blowing spray is observed the sea state is rough and the carrier will be steaming to maintain steerageway. The wind over deck will be gusty which will necessitate more frequent power and control corrections to maintain the glide slope. Turn earlier at the 180° position to avoid being long in the groove.

PATTERN
Enter with a level break from a course parallel to Foxtrot Corpen, close aboard the starboard side of the ship at 800 feet MSL. If in formation, maintain a break interval of 12 to 16 seconds. When on downwind leg, descend to 600 feet and perform cockpit check. Engage and check operation of the approach power compensator. Cross-check angle-of-attack and airspeed indicator. Check cockpit emergency ventilation port closed before using angle-of-attack indications. Fly a racetrack pattern with the 180° position approximately 1¼ miles abeam (check distance with TACAN, if desired) at 600 feet MSL. With a 30-knot wind over deck, begin the 180° turn to the final approach when approximately abeam the LSO platform. To be lined up with the angled deck centerline, roll out immediately to the right of the ship's wake. When the meatball is acquired, transmit call sign, fuel state (nearest 100 pounds), "Crusader" and "meatball." Signify no meatball by transmitting the code word "Clara."

GLIDE SLOPE
The physical glide slope projected from the ship is approximately 4°. Due to the wind over the deck, the aircraft flies approximately a 3.25° slope through the air. However, at any given point in the approach, the pilot is looking at the ship on a 4° slope. This, of course, gives the pilot the feeling that he is too high. This feeling should be disregarded, and only the meatball should be relied upon for proper glide slope control. Closure rate on the ship is on the order of 105 knots, whereas on the field, closure rate is usually equal to true airspeed (light wind). This difference in "distance/time" relationship further emphasizes the need for looking at, and flying the meatball all the way to touchdown, rather than estimating power required by looking at the deck. It is necessary to carry a little more power on the glide slope on the ship than ashore, in order to maintain the proper glide slope and airspeed.

FLYING THE MEATBALL
Use of the approach power compensator is recommended for all carrier landings. An occasional manual approach will suffice to maintain proficiency. The approach power compensator should not be used if operating in manual fuel control or if the wing cannot be raised.CAUTION
It may become desirable to make a manual approach, instead of an APC approach,
under unfavorable approach conditions such as gusty or extremely high winds.
The technique for flying the meatball during steady deck operation approximates that used during FMLP [Field Mirror Landing Practice or MADDLS in the old lingo Mirror Assisted Dummy Deck Landings]. However, with increasing rough seas the glide slope varies, particularly in the vertical plane. With a point-stabilized Fresnel lens, the glide slope is stabilized only to the extent that it passes through a point in space 1,800 to 2,200 feet astern (approximately half way out on the final approach). As the deck pitches, the glide slope deflects as necessary to remain focused on this point. It is apparent that the vertical movement of the glide slope increases in magnitude as distance from the focal point increases. With a line stabilized lens, the glide slope is stabilized for all ship movement except heave. No meatball movement due to deck motion should be discernible to the pilot, except under the most severe conditions.

Initial Approach
After rolling wings level on the final approach, begin a rate of descent of approximately 600 feet per minute. Average out the meatball movement. Maintain a glide path that shows the same degree, or distance, of meatball movement above and below the datum lights.

Middle Approach
As the aircraft progresses into the middle third of the approach, meatball movement due to carrier pitch is at a minimum. Use this part of the approach to advantage. Adjust nose attitude and establish the proper rate of descent.

Final Approach
As the aircraft moves into the final third of the approach, the meatball will again begin to cycle on the optical landing system. Hold the power setting and the rate of descent established during the middle third of the approach, unless instructed otherwise by the LSO. If the meatball goes high when approaching the ramp, do not attempt to center it. The ramp could be cycling down, and an increased rate of descent, coupled with a rising ramp on touchdown, could exceed aircraft design limits. If the meatball starts to go low, do not hesitate to override the approach power compensator by adding power. In this case, the aircraft could be descending below the glide path, or the ramp could be cycling up. In either event, the aircraft is getting too dose to the ramp and the only correction is power. Accept the fact that wave-off and bolter rates increase when landing with a pitching deck. The higher rates are acceptable, particularly when the alternatives are considered (hard landings, ramp contacts, etc).

FOULED-DECK WAVE-OFF
Don't anticipate a fouled-deck wave-off. Aircraft will repeatedly clear the landing area fractions of a second before the wave-off point is reached, and a clearance to land will be received. Let the LSO give the wave-off. Wave-off characteristics are good and the engine accelerates from approach thrust (about 84% rpm) to military thrust in about 2.5 seconds.

CLOSE-IN WAVE-OFF
Avoid a close-in wave-off whenever possible. However, if it becomes necessary, move the throttle smartly to MRT or CRT and maintain optimum landing attitude. Do not overrotate. Maintain a wings level flight attitude.WARNING
Accept a touchdown short of the number one cross-deck pendant, accept a bolter,
but do not overrotate and do not turn. In the event of a ramp strike, select afterburner...."
https://www.docdroid.com/3rcAqOj/vought-f-8a-b-crusader-flight-manual-pdf (40Mb)
https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1444x1050/pattern_vought_f_8a_b_crusader_flight_manual_natops_d1ed7553 c35ea2c528769d44090abcbb33110d21.gif

[sycamore]

Spaz,I assume the Approach Power Compensator was a `simple autothrottle`...?

[Wetstart Dryrun]

I would commend ' I want to take off from a carrier' by Dos Gringos, available on YouTube.

[NutLoose]

USN T45 carrier ops procedures.

https://www.cnatra.navy.mil/local/docs/pat-pubs/P-816.pdf

[SpazSinbad]

Only the A-4E/F had APC (when modified). The A4G in RAN FAA service did not have APC. I looked in the F-8 NATOPS & online info for APC knowledge but nowt, so the description from the Skyhawk NATOPS will have to do for now.

A-4E/F & A4G Skyhawk NATOPS 1968
"Approach Power Compensator
The approach power compensator (APC) system is installed in aircraft reworked per A-4 AFC 268-1-11-III. The APC controls the fuel control and is designed to maintain the optimum angle of attack of 17.5 units resulting in an optimum approach speed on the glide slope and during normal maneuvers in the landing pattern at any landing gross weight. Major APC components are the computer, amplifier, servo actuator, accelerometer, elevator potentiometer, angle-of-attack vane transducer, and the APC control panel.

The APC is designed to command throttle position between an approximate 70 percent rpm and an approximate military rated thrust (MTR) in response to angle of attack. The angle-of-attack signal is modified by normal acceleration and elevator control stick position. If the APC is engaged or operating when aircraft angles of attack are greater than or less than optimum, the APC will compensate by increasing or decreasing throttle position accordingly. At angles of attack greater than optimum, the APC will command an increasing throttle position until MRT (approximate) is attained or the angle of attack returns to optimum. Conversely, at angles of attack less than optimum, the APC will command a decreasing throttle position until 70 percent (approximate) rpm is attained or the angle of attack returns to optimum."

OneDrive: _A4G_NATOPS_Text_Searchable+BookMarks.PDF (139Mb)

[url]https://1drv.ms/b/s!AuYHBzTWY83LikE-9X8-vun4XQ5k?e=NWQNM8

[SpazSinbad]

Good PDF thanks (date 2019 - an earlier PDF is less detailed). Pics from the 2019 PDF
https://cimg1.ibsrv.net/gimg/pprune.org-vbulletin/1333x857/f_35armrestraintflightsuitsurvitec_272afd2519d6d61eb56b428a6 6911c3f49699342.jpg
https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/891x998/f_35_arm_restraint_system_for_ejection_f0347ade16a4d55029c9a cc8694caf6b5dcf78c7.jpg
2 page PDF has info from LM about AUTO EJECT for the F-35B plus info about dem 'strings'.
F-35 Subsystems Design, Development & Verification 2018
"Ejection System The auto-escape system is configured in the F-35B only for the event of catastrophic failure of the LiftFan®. Such a failure can produce a rapid onset of forward pitch accelerations, perhaps exceeding the pilot’s ability to react and manually eject. The system is designed to provide detection of inertial attitudes and rates in the pitch-down plane within tolerances to filter out normal flight control input and response. The detection occurs in the control law software application of each VMC [vehicle management computer] during conditions in which the system is armed."
"US16E arm & leg restraints A second feature of the US16E ejection seat is the active arm and leg restraint. To minimize injury due to arm and leg flail during ejection, the US16E actively restrains the pilot’s arms and legs during ejection. It uses fabric lines that are integrated into the pilot’s flight ensemble. During ejection, the legs are drawn back and the arms are drawn to the lap and held until the lines have been severed. Figure shows the US16E arm and leg restraint system."
https://cimg1.ibsrv.net/gimg/pprune.org-vbulletin/1180x1050/f_35ejectionseatrestraints_2a46a8db525fcc600c7aeb086c429418f 5e4d36d.jpg

[SpazSinbad]

Not being an ex-STOVL pilot I was intrigued to find more about STOs in light of the question about catapulting and wind direction earlier. Other PDFs have described from the test pilot viewpoint what is it like to STO from an LHA however this 15 page PDF addresses the 'WIND' question & other STO questions.
F-35 STOVL Performance Requirements Verification by LM & others staff 2018
"...An element of ship [USN LHA] operations that could not be evaluated during shore-based testing was the variation of ambient wind over the [flat] deck of the ship. The amount of headwind and crosswind the aircraft experiences during a STO is a function of the magnitude and direction of the ambient wind and the speed, pitch, and roll of the ship. It is also affected by the position of the aircraft along the STO launch tram line and its location relative to the ship’s superstructure. The environment can be very unsteady and unpredictable...."

[SpazSinbad]

Computational and experimental modelling study of the unsteady airflow over the aircraft carrier HMS Queen Elizabeth
Ocean Engineering Volume 172, 15 January 2019, Pages 562-574

https://www.sciencedirect.com/science/article/pii/S0029801818318705 (PDF 6Mb)

"...Fig. 25 shows computed mean streamlines over the bow of the ship in a headwind, demonstrating the smooth air flow and the effectiveness of the bow design....

...5.1. Air flow over the full-scale flight deck
Fig. 27 shows the mean air flow over the QEC in a headwind, illustrated by mean streamlines in vertical planes that are aligned with the oncoming wind and pass through the landing spots (spots 1 to 5 along the length of the deck and spot 6 behind the aft island). The streamlines are coloured by turbulence intensity....

...While it is preferable to launch and recover aircraft to the ship in a headwind, where there will be less flow disturbance over the flight deck and higher relative air speeds, and hence lift for the aircraft, there will inevitably be times when the relative wind will be from directions other than ahead. It is important, therefore, to have an understanding of the air flow over the deck for all wind directions...."
https://cimg6.ibsrv.net/gimg/pprune.org-vbulletin/1680x843/wodstreamlinesbowqeclassskijumpcfd_2f0e397ce5e5934a29fc00e30 dc4fd0170855661.gif

[SpazSinbad]

An excellent 25 minute fillum - although dated - explanation of USN Carrier Ops with the A-7 Corsair [reference to crabbing approach?]

"A-7 CORSAIR II FAMILIARIZATION" U.S. NAVY AIRCRAFT CARRIER FLIGHT DECK LANDING PROCEDURES 80184

https://www.youtube.com/watch?v=-je2fF1PURs

[JagRigger]

This just popped up on another forum

Legit ?

https://duncanblack.smugmug.com/My-First-Gallery/i-zmrq53D/A


https://cimg1.ibsrv.net/gimg/pprune.org-vbulletin/889x1200/46cb1397_5851_47c2_ab35_82558f27baee_6a2182344d714a43c1696fc 11321010898dc7d27.jpeg

[SpazSinbad]

Why not. I'm not familiar with serial numbers of UK F-35Bs as seen in this ZOOM.
https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1554x1121/itfallindawatah_11cfb738f1b860450ab61f503a6d33504ce3ae0f.jpg
https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/889x604/recovery_f_35b_uk_qe_ski_jump_crash_i_zmrq53d_x3_crop_e8a093 cdb48ef3a95b299ab36bde30af207db7b4.jpg

[Not_a_boffin]

ZM152 - that's the puppy.

[LowObservable]

Without belaboring the obvious, the airplane is upside-down. Since it probably didn't get flipped on the recovery, and given the likely scenario and the dynamics involved, one suspects that it flipped beyond the vertical before it hit the water. In which case the pilot may well owe his life to auto-eject.

[Timelord]

I think auto eject is only enabled during the hover.

[pasta]

Without belaboring the obvious, the airplane is upside-down. Since it probably didn't get flipped on the recovery, and given the likely scenario and the dynamics involved, one suspects that it flipped beyond the vertical before it hit the water. In which case the pilot may well owe his life to auto-eject.
It seems incredibly unlikely that a largely-intact aircraft is going to sink through a vertical mile of water and then come to a rest on the bottom in the same orientation it hit the water. Think what happens if you leave a poorly-trimmed aircraft to its own devices in the air.

[switch_on_lofty]

You can't infer anything about the angle of water entry from something salvaged on a deck. Add in the few km of water to fall through...

[212man]

It seems incredibly unlikely that a largely-intact aircraft is going to sink through a vertical mile of water and then come to a rest on the bottom in the same orientation it hit the water. Think what happens if you leave a poorly-trimmed aircraft to its own devices in the air.
reiterating the belief that most people think that the sea is only a few feet deep and has a sandy bed!

[LateArmLive]

I think auto eject is only enabled during the hover.
This is true. In this case, the pilot pulled the handle when it became obvious he could neither fly nor stop on the deck.

[LowObservable]

I think auto eject is only enabled during the hover.

I believe it is enabled in STOVL mode, including STO, because the same issue can apply - a burp in the powered-lift system can cause a rapid departure to an out-of-envelope attitude. LAL may have information as to this specific case.

[Navaleye]

Looks like one of the wheels might take to the air again so all is not lost.

[SpazSinbad]

FWIW wot is LAL? And FWIW some quotes repeated in this thread about STOVL MODE 4 auto eject in HOVER MODE:
F-35 Lightning II Cockpit Vision 19 Oct 2010 Michael Skaff [LM chief PVI Pilot Vehicle Interface Designer]
https://www.fujitsu.com/downloads/MICRO/fma/marcom/convergence/data/papers/2010-01-2330.pdf
“...In the unlikely event of catastrophic engine failure in hover mode the F-35 is equipped with an automatic ejection seat. This feature is only armed and available at the extremes of the vertical landing envelope. At first thought an auto-eject function seems extreme to most pilots, but once they are made aware of the time critical urgency and the total inability of the human to command a manual ejection during low altitude hover, most are thankful for this capability. This is a clear example of letting the computer do what computers do best....”
___________________________________

Martin-Baker: the JSF story so far 08 Mar 2011 Steve Roberts
JSG IPT Lead, Martin-Baker Aircraft Company Ltd - Synopsis of Lecture to RAeS Loughborough Branch
http://homepage.ntlworld.com/john.ollerhead/RAeS/Past_lectures_files/110308%20JSF%20seat.pdf
"...A typical pilot takes two seconds to react to the ejection klaxon or one second if warned in advance of a likely failure. In the case of a STOVL related failure, ejection must take place within 0.6 seconds. Hence it was necessary to install smart failure sensors on the aircraft to automatically fire the ejection circuit mounted in the back of the seat....”
____________________________________

Test Flying The Joint Strike Fighter 17 June 2011 Graham Tomlinson
http://myweb.tiscali.co.uk/hawkerassociation/hanewsletters/hanewsletter030nvu/testflyingjointstrikefighter.html
“...In the unlikely event of the lift fan failing catastrophically the aircraft would pitch inverted in 0.6 seconds, and the pilot is protected by auto-ejection signalled by pitch rate and attitude...”
___________________________________

F-35 Subsystems Design, Development and Verification
Drew Robbins, John Bobalik, David De Stena, Ken Plag, Keith Rail, and Ken Wall
[b]E. Ejection System...
...The auto-escape system is configured in the F-35B only for the event of catastrophic failure of the LiftFan®. Such a failure can produce a rapid onset of forward pitch accelerations, perhaps exceeding the pilot’s ability to react and manually eject. The system is designed to provide detection of inertial attitudes and rates in the pitch-down plane within tolerances to filter out normal flight control input and response. The detection occurs in the control law software application of each VMC [vehicle management computer] during conditions in which the system is armed."

[LateArmLive]

FWIW wot is LAL? "

I is LAL.....

[SpazSinbad]

LOL - Cool BEens LAL - some more quotable quotes for STOVL MODE 4 auto eject:
Punching Out Jan 2021 IAN PARKER - Combat Aircraft Journal Jan 2021 Volume 22 No 1
“...Automatic ejections
With some F-35B aircraft failures, the aircraft departure characteristics could be too fast for the aircrew to react in time. Roberts says: “With Lockheed Martin, we carried out a lot of system modeling to determine which conditions the aircraft could get into where the aircrew are not able to eject in time.

Certain failure scenarios were identified, however unlikely, where the aircraft was transitioning to and from wingborne flight in the STOVL mode. These conditions would require the aircrew to eject quicker than the fastest recorded reaction times for most aircrew. Based on this, the F-35B introduced an automatic ejection capability for the very first time in the West.”
________________________________
When All Else Fails 22 Dec 2013 Mark Ayton ["outlines the life-saving ejection seat"]
[magazine special a decade or so ago about the F-35]
"...The STOVL aircraft propulsion configuration results in unique failure mode conditions, which the pilot is not able to react to quickly enough to eject manually. This resulted in the US16E seat interfacing with Lockheed Martin’s auto-eject system which caters for low-altitude, low-speed and adverse pitch attitude escape conditions...."
_______________________________
Martin-Baker: Saving Lives in the Family Way 15 Jun 2015 Chris Pocock
https://www.ainonline.com/aviation-news/defense/2015-06-15/martin-baker-saving-lives-family-way
"... the F-35B version of the Lightning II has an auto-eject mode. This is designed to function in the specific instance where the STOVL aircraft is in the hover, and the shaft-driven lift fan fails. In that case, the jet is likely to pitch down sharply, quicker than the pilot can react to fire the seat manually. It will therefore fire automatically while the possibility of escape remains...."
_______________________________
Jane’s features WFEL’s F35B ski jump’s involvement in HMS Queen Elizabeth trials Oct 2017 Richard Scott
https://www.wfel.com/en/news/janes-features-wfels-f35b-ski-jumps-involveme/1008
"...QinetiQ flight test engineer Gordon Stewart, who has spent much of the last five years attached to the joint US/UK F-35 Integrated Test Force at Patuxent River, points out that making STOVL easy was an important design consideration for the F-35B control law. “Because of the high level of automation embodied, a ski-jump launch is in fact the most straightforward take-off manoeuvre for the STOVL variant of the Lightning II,” he explained to a Royal Aeronautical Society audience in May this year. “When the pilot slams the throttle, the control law is configuring the aircraft for maximum acceleration.”

At the point the aircraft accelerates up the ramp, the control law detects the change in pitch rate and attitude. “That’s the point where it transitions into ski-jump mode,” Stewart said. “Once that occurs, the aircraft has approximately one second to transition to flyaway.”

During that brief period, the control law is configuring the aircraft to minimise the pitch transient on exiting the ramp. It achieves this by setting the horizontal tail position, repositioning the angle of the engine nozzle, and changing the balance/rate of thrust between the lift fan and the aft nozzle. “The thrust split moves forward on the ramp, then back after exit,” said Stewart. “That rapid change in ratio to balance [the aircraft in airborne flight] reflects what’s happening coming off the ramp....”
_____________________________
F-35B begins new ski-ramp testing campaign c.18 Jul 2017
http://www.janes.com/article/72352/f-35 ... ign=buffer [lost right click for mouse?! - impossible to use Windows without RIGHT CLICKING!]]
"...[ Pete ‘Wizzer’ Wilson, BAE Systems F-35 STOVL lead test pilot] The F-35B flight control law mode incorporates a so-called Ski Jump Short Take Off (STO) Mode. There is no action on the part of the pilot to engage it, other than to ensure the aircraft is steered up the ski jump; rather, the mode is enabled when the Control Law detects the rotation and rotation rate as the aircraft accelerates up the ski jump."
__________________
F-35 Flight Testing At Pax 15 Oct 2012 Eric Hehs
F-35 Lightning II Flight Testing At NAS Patuxent River | Code One Magazine (http://www.codeonemagazine.com/f35_article.html?item_id=110)
"...The flight control laws for the STOVL variant have six modes that are associated with specific actuations. Mode 1 defines conventional flight. Mode 4 defines STOVL. The other four modes define transitional states between the two primary modes...."

[SpazSinbad]

2 page PDF from 2013 & VX-23 about measuring CVN WOD with an annannannaaemmeotobemmometer accuratetly beKuz youse PALS by LCDR Pat “WHO?” Bookey USN - spoiler alert - FWD is da bestest when they call the wind moriah.

[downsizer]

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1176707/Service_Inquiry_Loss_of_F-35B_Lightning_ZM152_BK-18.pdf


Full SI at link.

[dervish]

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1176707/Service_Inquiry_Loss_of_F-35B_Lightning_ZM152_BK-18.pdf


Full SI at link.

Thanks for that downsizer.

My brain hurts after a few pages. Everything is in past tense, and the pilot is not a he or she, but a they. So are some of the individual engineers, but not all of them. I haven't worked that one out yet! The investigation itself must have been easier than getting the strangled grammar right.

[Davef68]

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1176707/Service_Inquiry_Loss_of_F-35B_Lightning_ZM152_BK-18.pdf


Full SI at link.
I'm amused they redact the numbers of 617 aircraft and the USMC squadron numbers and designation, when both were widely available, not least in the TV documentary!

[madhon]

Thanks for that downsizer.

My brain hurts after a few pages. Everything is in past tense, and the pilot is not a he or she, but a they. So are some of the individual engineers, but not all of them. I haven't worked that one out yet! The investigation itself must have been easier than getting the strangled grammar right.

Why have they blanked out the number of RAF and USMC jets embarked, and that the USMC where embarked at all when its common public knowledge that they where and how many jets where.

[Asturias56]

they've also blanked out identification of various bits of the ship (such as the lifts) which can be found in many publications - crazy...................

an interesting insight into the minds of "security"

[sycamore]

And all it needed was a length of `Pussers`rope to link all the `red bits `together,and a `shadow board`....bit of basic engineering....

[Bengo]

I am simply amazed that non-fitment of the blanks whilst on deck could become an approved SOP.

OK the blanks are not good. Address the problem locally with short-term fix ( pushers string, shadow boards et al) and kick off up the chain. If not identified by the IFTU, SAT (Air), OST and FOCFT should all have been ideal vehicles to get the problem publicised.

N

[WHBM]

... and the pilot is not a he or she, but a they.
That's actually quite reasonable. It avoids the cumbersome 'he/she'. And if you stick with gender-specific, and say 'she' when relevant, and there is only one female pilot in the group, it immediately identifies them. Which is not what is desired.

[Chugalug2]

That's actually quite reasonable. It avoids the cumbersome 'he/she'. And if you stick with gender-specific, and say 'she' when relevant, and there is only one female pilot in the group, it immediately identifies them. Which is not what is desired.

This is yet another example of sledgehammers used for nut cracking. If your "Which is not what is desired" is indeed valid there have always been alternative options; "the pilot", "the controller", etc, without having to call every individual a "they". Perhaps this strangulation of the English language is more fitting in the Wigston legacy thread than in a UK military aviation air accident report?

[Davef68]

they've also blanked out identification of various bits of the ship (such as the lifts) which can be found in many publications - crazy...................

an interesting insight into the minds of "security"
And the ski ramp!

It's interesting to note that rather than being 'embeddded' the blanked out non-UK forces seem to have been very much doing their own thing. Perhaps why they were blanked out

[Thrust Augmentation]

What a farce, at least the report kept someone in paid employment for a few months...

[ORAC]

https://twitter.com/intercityfc/status/1690021970727825408?s=61&t=rmEeUn68HhlFHGKbTPQr_A


🧵following the release of the UK Ministry of Defence Service Enquiry into the loss of F35B Lightning ZM152 from HMS Queen Elizabeth during the Carrier Strike Group 2021 deployment. Focus for 🧵is on workforce issues, principally insufficient personnel leading to fatigue.

The UK F35 workforce was insufficiently resourced from inception. This has led to an inability to generate the required Operational Capability. This is not just about Pilots, it’s the entire workforce.….

​​​​​​​https://threadreaderapp.com/thread/1690021970727825408.html

[LateArmLive]

The UK F35 workforce isn't just insufficiently resourced, but struggling to retain SQEP after working themselves to death over a short tour with very little to show for it. The entire model needs re-working.

[Bob Viking]

I realise I could be shot for saying this but as an outsider nowadays I can’t help thinking that the best solution for UK Armed Forces is to shrink.

We can’t afford to pay, house and equip what we have and we seem unable to recruit properly to fill the vacancies. I think it’d be better to have a smaller, better paid, better equipped and happier force that can do what it does well, instead of trying to always do too much with too little.

BV

[Timelord]

And stop pretending that we are a global player with a total armed forces strength of fewer than 150,000. (As an aside, the NHS employs 1.4 million and apparently needs more)

I always admired the Dutch, Danish, Norwegian air forces. They did a lot less than us, but they did it really well and all seemed to be pretty content with their lives, unlike us even in “my day”.

[Arthur1815]

I realise I could be shot for saying this but as an outsider nowadays I can’t help thinking that the best solution for UK Armed Forces is to shrink.

We can’t afford to pay, house and equip what we have and we seem unable to recruit properly to fill the vacancies. I think it’d be better to have a smaller, better paid, better equipped and happier force that can do what it does well, instead of trying to always do too much with too little.



BV
If said reduced force had units manned to establishment they would be ripe for ‘efficiencies’ to continue the downward spiral.

[Geriaviator]

Ah yes, but our VSO strength is the envy of most countries.

[Asturias56]

certainly in numbers - but in quality............ maybe not................

[Jobza Guddun]

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1176707/Service_Inquiry_Loss_of_F-35B_Lightning_ZM152_BK-18.pdf .

Interesting. The workforce issues weren't / aren't a surprise to read about and are set to get much worse. TG1 has struggled increasingly since SDSR 2010, and the long-expected pigeon is roosting. The highlighted shortages and fatigue are being exacerbated by growing inexperience and also a dilution of resilience. The report suggested to me that 617 did not quite have its boat practices together - that may well underline the challenge of a hybrid RAF Sqn going to sea compared to, say, a Merlin NAS, where shipborne practices and husbandry are far more likely to be endemic. Hopefully they're much sharper now, which would be the whole point following an avoidable loss!

[Big Pistons Forever]

As an X Navy man most of the aircrew I met were stand up guys/gals who just wanted to get the job done but I was never sure whether to be in awe, or disgusted with at the chutzpah of some aircrew. I usually settled for an amused sigh. My one "win" on this one was with the helicopter support on a domestic flood assistance op. I was informed that the helicopter was u/s and the crew was going to stand down until a repair crew could be flown in the next day. Excellent I said all the crew can report to my PO for sand bag filling duty. Amazingly about 10 minutes later I was informed that the helicopter could do one more flight to the Air Force base for repairs. Sorry I said no can do as I talked to the OTC and he is not going to take the risk, we will wait for the repair crew tomorrow.....and thanks for helping the lads with those sandbags. :E

[Two's in]

This follows the trend of many recent SIs. It's undoubtedly detailed and considers a multitude of factors, but as Sycamore says upthread, the correct engineering process or procedure for preventing aircraft operation with non-flight equipment fitted ("Red Gear" in this saga) has been available since the dawn of time. Segregating the Red Gear between each aircraft, meticulously recording fitment and removal of the complete set, and taking basic precautions to integrate complete sets (pussers string or black marker) would have prevented this and there is nothing new in any of those techniques. By filling the SI with all the distractions (or life on operations as we know it) it makes it seems like a really complex puzzle to solve, instead of saying "this was a basic but fundamental pre-flight task that was overlooked by everyone involved, resulting in the loss of the aircraft". I would also be interested to know how the security pressures versus flight safety argument played out. In this case, it looks like flight safety lost.

[sycamore]

I would have thought that ,particularly when `embarked` that each aircraft had a `plane captain`(engineer) for each cab,and a small crew...it was `their aircraft`,they were responsible for it ,whether it was u/s or not.And on deck,the `p-c` ran a checklist to ensure the aircraft was ready to fly.Working on a busy flightdeck is totally different from on an airfield,even dispersed.
And another thing,why launch the aircraft from so close to the ramp...it seems that ,if you launch from further back,you get better acceleration,longer run,more time to check the power/accel rate,and maybe better ability to stop.....I was always of the impression that `runway behind you is wasted`..use it`!

[Just This Once...]

I would also be interested to know how the security pressures versus flight safety argument played out. In this case, it looks like flight safety lost.

Security didn't win either. In a futile attempt to prevent a mythical long-range photo-op compromise of the intake and exhaust they manage to drop the whole thing into international waters.

Yep, we got the thing back but it must have been tempting to fling the security folk over the ramp to guard it.

The RN Officer cadre used to have a good reputation at the people stuff. Now we have captains who think a mass service on the flight deck at 40ºC plus, on a deck surface known for scorching temperatures, is a good idea. Only 20 or so casualties, so that's ok. Got to keep morale up eh.

[fdr]

That accident report is up there in the most tortuous use of language applied to a report in recent times. Are the authors native English speakers?

The fact that this item was fished out of the still floating soon to be reef probably explains why the fleet was not grounded immediately.

https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/716x1002/screen_shot_2023_08_13_at_12_03_54_pm_ac125b2ecd914a15d2df18 1db8c079844c83f3e1.png

This has to be the most expensive engine blank in history. (Homer would add, "the most expensive engine blank in history... yet!")

The nonsense applied in the interests of security appear to not concern themselves with the consequential risks that arise from those very security processes.

If the engineers task processes are to be achieved reliably, then need to work without interruption to work flow. None of that happened, there were known breaks in continuity, and there was no mitigation strategy in place, something, like, I dunno... start again from the beginning or similar. At least the pilot should have been able to identify that the LH blank was still in place, assuming that any walk around was actually conducted, after all, secrecy and all that, was he permitted to be aware that the aircraft was actually there? No observer was able to detect the blank was still in place, as there are no observers, (refer security).

The description of the cage for the stowage of the "Red Gear" items conjures a chaotic stowage of items that are known to be critical for flight safety if missed, and yet... it appears to all be bundled into a pile. Sad that there was no shadow board in use that all items fitted needed to be accounted for before the pilot goes walking out to the bird to not do an effective walk around of. That might be a revolutionary idea, after all, we have only been doing that for about a century for aircraft engineering.

The blanks on the tailpipe were reported in this short snapshot of operations to have been variously, dislodged and found on the deck or, noted to be lost at sea... at what point do the guys stop and think about the subject in a holistic manner, as it appears this has issues at both ends of the bird. the intake blanks had no streamers on them, even the words had been removed of "REMOVE BEFORE FLIGHT" as they were being dislodged, and were considered a FOD hazard, but the blank itself was not?

Even with the redactions that appear to be random, but which include the actual event itself, this is a depressing report.

Sometimes you just have to be embarrassed to be in the same business.


But, at least the important stuff got done, the canopy transparencies were nicely free of salt spray, all the way until the plane got tossed into the Mediterranean.

The Security officers went a long way to not show the intakes, far enough to result in the plane being tossed into the water, and then the powers that be do the report, declassify the report and show a close up of the very intake that the SSO was so damned concerned over. Rest easy though, the intake design is pretty much exactly what would be expected with a design that has a need for LO, and has to work around a vertical plenum chamber right where you don't want it to be. That of course makes for fun flow control, which has a limited number of solutions due to the LO requirement, and so should not be seen, as indeed, they are not. The F-35 is not the first aircraft to have an air intake... not even the first LO air intake, but at least, the red gear stopped some long range photos from some AGI or fisherman's iPhone, at the cost of a 2 year recovery program and a CAT-5 bird.

That there had been at least 4 other events prior to this on the F-35A, B and C models that did not cause an accident seems to suggest that there is room for better information flow across the program so that others may learn and not have to repeat a failure that has been done many times before. The preceding B model event was the 3rd occasion that engine runs had been conducted by the same aircraft with the blank in the intake.

The report shows clearly that if the pip pins were not holding correctly, a blank could be dislodged and enter the engine intake and become hidden inside the intake, behind the lift fan plenum. That information was not known prior to the event, in spite of multiple events across the other operators fleets with having blanks still in the engine. It makes it imperative to have obvious configuration control in place for all matters before an accident shows that it is necessary. The operators take care for gear pins and seat pins etc, but all of these have come along after the event, as this one now does too.

https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1200x769/screen_shot_2023_08_13_at_12_29_56_pm_d074428d1ad5dabd5ce9c5 dd77141cf828f9a91e.png

[megan]

fdr, one does have to smile that a device designed to prevent the ingress of fod does itself become fod. Still, not alone, company Huey had a piece of the installed metal fod screen fail due fatigue and cause an engine out ditching.

[Asturias56]

the blank must be the lowest cost, simplest bit of the whole shooting match and yet they didn't have a way to ensure it stayed in place or remain visible..... it's unbelievable - but it happened..................

and that report......... :ugh:

[Brain Potter]

I’ve yet to see such a badly-written SI report.

This is apparent from the very first sentence written by the board which says that the aircraft ‘ditched’. The MRP doesn't appear to have a definition of ditching, but the CAA say:

Ditching is a deliberate emergency landing on water, it is not an uncontrolled impact. Ditching events beyond coastal waters are rare, but experience suggests that if the aircraft impacts the water under control, the chance of survival is high.

The aircraft was unoccupied and uncontrolled when it hit the sea. In aviation terms that are widely used and understood, this accident was a crash not a ditching, After opening with such fundamental error, I suppose that the poor quality of the rest of the report should come as no surprise.

[Asturias56]

Got the impression they were tying themselves in knots to avoid saying anything clear.................. and of course there is a no blame requirement

[Asturias56]

"Sad that there was no shadow board in use that all items fitted needed to be accounted for before the pilot goes walking out to the bird to not do an effective walk around of. That might be a revolutionary idea, after all, we have only been doing that for about a century for aircraft engineering."

Yup - you see it in your local machine shop and garage but on a multi Bn $ carrier - no........

[fdr]

I’ve yet to see such a badly-written SI report.

This is apparent from the very first sentence written by the board which says that the aircraft ‘ditched’. The MRP doesn't appear to have a definition of ditching... .

dribbled, drooled, plummeted... plonked.... something with a bit of onomatopoeic poetry would have worked.

I am still non plussed by the redactions... there be redactin' happenin', and then the data that indicates what was central to the block o' black shows up in a photo or a graph, like the thrust output from the engine. Was there a time limit on this going out the door for the powers that be? It is a most peculiar report, written by they/those riters.

FYI, I feel for the troops involved, the whole effort seemed a circus, a sit down and briefing upwards from the troops to their bosses might have gone a long way to avoiding the expensive lesson that was learnt herein, and yet, I fear that the systemic issues that arise in this case are not taken on board by the powers that be. Within a system that is a goal oriented focus, where it is not acceptable to say no, devolution is the most probable outcome. Yes, there are reporting systems, but at what point do they result in interdicting a process that is throwing out flags with abandon?

The safety equipment issues raise further concern IMHO, half a life jacket even when not required should raise eyebrows, and that is following other recent matters of the same flavour on the Hawk. The RH arm restraint failing, this is stuff that ​ there needs to be a fair level of confidence in​, and while credit is given for identifying the failures, how about working on why there are failures in systems that should not fail.

There are smart people in the mob, reasonable solutions can be made to protect the machine, RAM finishes, pilot, and the engineers if there is a will to do so.

​​​​​

[charliegolf]

Got the impression they were tying themselves in knots to avoid saying anything clear.................. and of course there is a no blame requirement

The only thing I got out of it really.

CG

[alfred_the_great]

I suppose one of the things it severely challenges is the fantasy that is the F35 routine operating model - the lack of sustained SQEP in embarked operations is writ large.

[Big Pistons Forever]

Two things struck me about the report

1) The impact manning instability had on F 35 operations. This is become real issue for many if not most of the Western militaries. Recruiting shortfalls and previous decisions to outsource and right size staffing to save money are coming home to roost in a myriad of bad ways.

2) The report said the pilot found and removed the gear pins on his walk around. This rather basic part of preparing the aircraft for flight appeared to have been missed by the ground crew. I wonder if this is anther indication of the issue I raised at point 1

Flight safety needs the right people in the right places with the training, time, and tools to do their job. It would seem, at least on this cruise the RN was Ohh for Three

[idle bystander]

Two things struck me about the report
Flight safety needs the right people in the right places with the training, time, and tools to do their job. It would seem, at least on this cruise the RN was Ohh for Three
True to some extent. The ship's Air Engineering Department seems to have had many faults, and if I had been the Cdr AE I would have expected to be sacked if not court martialled.
But the extraordianary incompetence and amateurishness of the 617 squadron engineering organisation that is the primary cause of this accident beggars belief. It is hard not to conclude that a major factor behind this sorry tale is the split responsibility between the two services. Naval aviation is best done by those with the experience and understanding to do it properly.

[Timelord]

But the extraordianary incompetence and amateurishness of the 617 squadron engineering organisation that is the primary cause of this accident beggars belief. It is hard not to conclude that a major factor behind this sorry tale is the split responsibility between the two services. Naval aviation is best done by those with the experience and understanding to do it properly.

Maybe, but let’s not make this an inter service thing. Don’t forget that 617 is half RN so the people involved may well have been dark blue, as was the pilot.

[Geriaviator]

One hopes that similar importance was given to equality and diversity requirements. After all, airworthiness is only one facet of today's RAF.

[Bengo]

I don't think this is an inter service thing. It is choosing the wrong horse for the course, or the wrong trainer. Marham, with the best efforts of both shades of blue, failed to deliver an effective seagoing Squadron. Why would anyone expect it to? It was asked to deliver something it was not experienced at. I suspect that if you gave Yeovilton the task of standing up the Typhoon force they would do just as badly.
That said, there used to be checks and opportunities to catch the errors. The Flight or Squadron formal ORI was the first. OST was the next. Hen it was over to the ship's QA team to make sure that QC was happening. To support that the Staff were out and about, reporting directly to the Admiral who was responsible.

This whole system appears to have fallen apart.

N

[Big Pistons Forever]

The cynic in me figures the end result will be to throw a few low ranking techs under the bus, develop some hugely bureaucratic and impractical to execute processes around the handling and stowage of aircraft protective covers and totally ignore the resource and manpower restraints that are IMO, the root cause of this accident......

[Asturias56]

I was rather intrigued by the vast importance given in day to day activities to making sure no-one, but no-one, saw inside the intakes. :cool:

they were clearly paranoid about the bad guys taking some long range pics as they transited the Suez Canal and the emphasis on restricting access to the deck at all times seemed so important that it over-rode any reasonable efforts to prepare the aircraft properly

[artee]

I was rather intrigued by the vast importance given in day to day activities to making sure no-one, but no-one, saw inside the intakes. :cool:

they were clearly paranoid about the bad guys taking some long range pics as they transited the Suez Canal and the emphasis on restricting access to the deck at all times seemed so important that it over-rode any reasonable efforts to prepare the aircraft properly
They didn't want anyone to see that there was a diminutive punkah wallah in there... :O

[Davef68]

Security didn't win either. In a futile attempt to prevent a mythical long-range photo-op compromise of the intake and exhaust they manage to drop the whole thing into international waters.
.

And then include an unredacted photo of down the intake in the report (fig 1.4.4)

[LowObservable]

Obviously it was all vewwy vewwy secret. Hey, what's a black Omega doing over here?

https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/950x715/serpentine_10f8b73f9a20cf2f5f02ba7cc62a9342a31da28b.jpg
https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/1038x783/serpentine2_29f256a90576fac6591a7a84a28e45ee64719e8b.jpg

[Thrust Augmentation]

Hey, what's a black Omega doing over here?

Things must be tougher than I imagined if MIB are running about in 20 year old cars.

[ORAC]

A good article - apart from the part suggesting that the RN is sharing their assets with the RAF.

As a reminder, the RN entered the JFH and started using the GR7/GR9 as they couldn’t afford to replace or man the SHar. It was the RAF who had to start sharing their Tornado strike replacement, not the other way round. And if the RAF starts to buy more Typhoons, or F-35A, as a strike assets, it is the RN who will lose their ability to quickly deploy to a carrier to reinforce the FAA…

And the RN can’t afford to buy, man or maintain the F-35B force out of their own budget.

https://x.com/edwardkeyjf/status/1695016945039405105?s=61&t=rmEeUn68HhlFHGKbTPQr_A

The F-35 accident report – a reality check for UK Carrier Strike

[Asturias56]

Jeez - and I thought the RAF and the FAA were on the same side.....................

[tucumseh]

couldn’t afford to replace or man the SHar.


I think one has to place the FAA's inability to support SHAR in context.

The policy whereby all Air Systems support funding was transferred to the RAF (AMSO at the time) meant the FAA lost control of its own funding. AMSO took over all procurement. (You think MoD's procurers do the procurement?!)

AMSO immediately lumped the two pots into one, and said 'First come, first served'. There was a very long queue of RAF 'requirements', but few if any FAA because they didn't have a physical presence for anyone to actually get in the queue. They'd been told to butt out and let AMSO run the show.

Within a short time the SHAR fleet was down to half a squadron fitted with (e.g.) their full nav fit. To generate more funding for the queue AMSO had simply scrapped it, changing its classification from 'repairable' to 'consumable'. I had to give evidence to a BoI about why a SHAR didn't have the kit necessary to find its way home after a major problem. Most of the RN were completely oblivious to these goings on. One example among scores. SHAR never recovered.

As an important aside, this squandering of money on what was desirable, not what had been bid for and approved, is what led directly to Nimrod MRA4 being scrapped. AMSO (by now AML) would no longer deliver what the MRA4 programme had been told to assume they would. (Setting aside for a moment that there was no valid approval to proceed with a Nimrod upgrade).

[idle bystander]

Jeez - and I thought the RAF and the FAA were on the same side.....................
Whatever gave you that idea?
As the report makes clear, naval aviation is an order of magnitude more complex than operating from a land base, and nothing like "just flying from a mobile airfield". It needs to be done by professionals, or not at all. Time for another Inskip, I feel. (Fat chance!!)

[SATCOS WHIPPING BOY]

1.3.72. ... the pilots wore their helmets throughout the walkaround. BK-18's pilot noticed the undercarriage pins were still installed, removed them and handed them to the see-off team.

1.4.42. ... the see-off13 team was cleaning the canopy as the pilot arrived at BK-18. The pilot then conducted a walkaround of the aircraft, electing to remove the undercarriage pins in the process.

I am not familiar with F35 see-off procedures but would the pilot have expected to see undercarriage pins still in as he did his walk round? Should they have been already removed at that point?

[CAEBr]

It's not immediately clear, but the fact that it is mentioned wrt BK18 and nothing is said either way for BK21 suggests to me that the pilot would have expected them to have been removed.
I also note in the convening authority remarks at 1.6.11 it refers to "two recent incidents with undercarriage pins" while discussing failure to follow process which would also point to a potential irregularity, although i have no knowledge of those incidents.

[SATCOS WHIPPING BOY]

It's not immediately clear, but the fact that it is mentioned wrt BK18 and nothing is said either way for BK21 suggests to me that the pilot would have expected them to have been removed.
I also note in the convening authority remarks at 1.6.11 it refers to "two recent incidents with undercarriage pins" while discussing failure to follow process which would also point to a potential irregularity, although i have no knowledge of those incidents.
Thank you.

[lefty loose]

Can anyone confirm what should have happened to BK 18, the report begins, continues and ends in the same convoluted and unclear manner

Red Gear employment policies

1.4.58. To bring conformity to the see-off procedures at RAF Marham a see- off Air Engineering Standing Order (AESO) was created with more detail than the Joint-Service Technical Documentation (JTD) section for 'Aircraft Dispatch Actions (ADA) —Inspections'. The JTD instructions directed that the intake and exhaust should be inspected for FOD but did not explicitly state how to do this. In the REDACTED and the REDACTED who operated the F- 35B and F-35C respectively, the see-off team conducted a check immediately prior to the pilot getting into the aircraft. An engineer climbed into the common duct to check for FOD, a process known as 'diving the duct' which, when completed, was reported to the pilot on their arrival at the aircraft. The JTD did not explicitly instruct the engineer to 'dive the duct,' but the text did include instructions for entering the duct safely and matched those required for the engine intake inspection.

1.4.59. This action of 'diving the duct' was not stipulated in the AESO see- off procedure. In the UK, engineers inspected inside the common duct during a POS/BOS, but this servicing was valid for up to 24 hours. There was no further check in the intervening period before the aircraft went flying. Fitment of Red Gear should have subsequently protected against FOD entering the intake, but as Red Gear was not routinely fitted whilst aircraft were on the flight deck, continuity of protection was lost.

1.4.60. The AESO stated that the see off team should report to the pilot:

'... this is BK-** (as appropriate) all Red Gear has been removed and accounted for and the 3 groundlock safety pins have been removed, placed in the Pin Bag and stowed within the MIP Panel'.