JetRanger crash Honolulu HI

[MikeNYC]

What looks like a Bell JetRanger (corrected) just crashed in Honolulu Hawaii. No fatalities, but one individual in critical condition. There's a video of the crash:

0sTTGlqZDx0

Edit: link to news story: http://khon2.com/2016/02/18/emergency-crews-respond-to-downed-helicopter-in-waters-near-arizona-memorial-2/

[RINKER]

Can the 206 loose drive to rotor system. Sprag failure.
Looks like power drive loss not engine failure.
Or Pax putting hand on collective

[John Eacott]

That is definitely a JetRanger, not a LongRanger. No vertical fins on the stabs.

[MikeNYC]

Good catch. Will update post.

[army_av8r]

My personal gut feeling says this looks like a main driveshaft failure, that failure results in the transmission no longer receiving input drive from the engine and the rotor subsequently drooping, but the engine is still producing power to drive tail rotor through the tail rotor drive shaft, this would account for the rise in engine noise while also seeing a left yaw, and simultaneously drooping the rotor.

[ersa]

Drive shaft failure or the collective had no friction on and dropped

[John Eacott]

What appears to be an approach to land precluded the loss of control and ditching. There isn't a helipad there, so it would indicate an in-flight problem that made the pilot initiate a precautionary landing.

A quick on-the-spot summary by the bloke who videoed the crash:

BeZN-7cKlrc

[mickjoebill]

According to trip adviser, some of their tours can be ordered with doors on or off.
In this case it looks like the doors were off.

Thank the stars/god/luck

In respect to doors off tourist flights what rules are in place in respect of securing passengers and their cameras?

A standard quick release seatbelt buckle can inadvertently be snagged and opened by a camera strap.
Whilst it's rare for a camera to be dropped, smart phones are the opposite.

The bloke who shot the video says he saw the helicopter fly low straight toward him and that he had enough time to get his video camera out.

Aside from the crash :( does this tour normally fly low level?

Mickjoebill

[John Eacott]

MJB, no they don't fly low level. That video appears to show an unplanned approach to a precautionary landing at an open area.

Just to throw a bit more Monday morning umpiring into the equation: no floats on a Jettie carrying pax on extended overwater ops. Really?

[mickjoebill]

Assuming it was a straight in approach the landing site, I assume, is pictured behind the report from the videographer.
(The crash occurred behind the curve wall)
It looks like public space. The sound of members of the public can be heard on the video so perhaps the pilot aborted the emergency/precautionary/landing to avoid the public?

Mickjoebill

[no_one]

I think that the footage was shot from the site of the Perl Harbor memorial shown in the link below.

https://www.google.com/maps/place/Hawaii/@21.366611,-157.9400235,74m/data=!3m1!1e3!4m2!3m1!1s0x7bffdb064f79e005:0x4b7782d274cc862 8!6m1!1e1

I dont think that there is a helipad nearby and so rather than a failure late in the approach it was an attempt to (emergency)land in the open area aborted when he got closer.

[Arnie Madsen]

.

VRS ??????????????????

[Delta Torque]

Driveshaft failure? There is a change in engine note, and apparent reduction in RRPM.

[Arnie Madsen]

.

Gotta be VRS ... high hover , low speed , probably a wind shift to boot .... watch the yellow police tape behind the guy in the second video (post 7) ... wind shifts 180* several times ...

[Heliringer]

Arnie, you need a pretty large rate of decent to get into VRS and this Helicopter didn't have that until something mechanical happened. I would look at the bushes behind the guy to get an Idea of the wind not the tape that someone is probably holding onto or people passing through a bit further on..

I've got no idea what caused it but it's not VRS or the other classic "no friction on the collective and it's dropped" from a poster above.....Really?

[Gordy]

FWIW.... I flew tours in Hawaii for 7 years albeit not on Oahu.

It apears to me that he is making a normal approach to a Helipad----a helipad that is not normally used by tour helicopters.Therefore it would indicate he "may" have had reason to fly there.... i.e. some sort of problem.

On final approach, something happens that causes the helicopter to descend rapidly.... this is NOT "settling with power".

Listen to the sounds.....

My educated guess is some sort of shaft failure or governor failure.

[cattletruck]

Judging by the engine speed and tail variations near finals I also agree the sprag clutch was playing up and "went off" again on approach to an emergency LA.

Could easily have been a much worse outcome.

[Madbob]

I think they were lucky that this happened over water and that the doors were off. Had it impacted terra firma with that ROD then there would have been fatalities or severe spinal injuries at the very least.


As to the cause we'll have to wait and see; one thing for sure it was very sudden and probably an irrecoverable situation for the pilot.


I hope the critical pax pulls through.


MB

[Heliringer]

Quote Scattercat
"To me, the rapid ROD from the "point of failure", is more indicative of a sudden collective pitch change, rather than simply the loss of drive to the rotor system. If the collective was held, in what would normally be a relatively high position given the approach phase, followed by a loss of drive, I would expect to see an engine over-speed & an increase in the ROD, but not that sudden. Collective control failure perhaps?" Quote Scattercat

Are you serious dude? If you lose drive to the rotor system and hold the collective in position and you will drop like a brick. The RPM decay is massive in the event of a total drive or proper engine failure. These things tend to fly better with rotor RPM, when you lose it, you lose flight.

[ersa]

Heliringer......

You need to calm down , you don't need a "pretty large " ROD to get VRS.

I suggest you do some reading

[Rotorbee]

Depends what you think is "pretty large".
http://www.x-plane.org/home/bretts/vrs2.jpg
For the TH-57 it is 722 ft/min somewhere around 35° decent angle and 1075 at 90° with the appropriate air speed.

[Heliringer]

ersa, I would calm down if some people didn't spout garbage!

He is into wind, got forward airspeed, he is decending in what looks like a normal but maybe cautious approach.

Helicopters make this type of approach all day everyday and don't get into the dreaded VRS. Why do you think he did?

However, on this occasion something mechanical went wrong it lost the RPM required to fly and dropped like a stone. They are very lucky to have had no fatalities at this stage.

[ersa]

Heliringer...

I never did ....just take a chill pill....hope you don't work in a multi crew environment

[robmelvin]

I'm a fixed wing student pilot so don't have a huge amount of knowledge on helicopters. Just wondering if one of you guys could answer a question? If that was indeed a drive shaft failure, and he had more altitude, say a couple of hundred feet, would he have been able to perform an autorotation? Was the biggest problem here his lack of altitude while making his approach and it all went wrong at the worst time?

[Thomas coupling]

TR flicker shown on video reverses its direction, sound of drive train change - TRF, methinks.

[Soave_Pilot]

TR flicker shown on video reverses its direction, sound of drive train change - TRF, methinks.

The reversing of rotation could be a camera optical illusion due to camera frames and rotation of the rotor, as the TR rotor slows down that comes in effect.
If I were to bet my chips on it, Drivetrain failure would be it, notice how the MR slows down too.

[Lonewolf_50]

[/URL]I'm a fixed wing student pilot so don't have a huge amount of knowledge on helicopters. Just wondering if one of you guys [url]http://www.bing.com/images/search?q=h-v+diagram&view=detailv2&&id=8D7B51D943857E84B80165FBFE3CA0BA78A91DF8&selectedIndex=2&ccid=6YcuchdV&simid=608016466325015193&thid=OIP.Me9872e72175587a067af16f0b2f83282o0&ajaxhist=0could (http://www.bing.com/images/search?q=h-v+diagram&view=detailv2&&id=8D7B51D943857E84B80165FBFE3CA0BA78A91DF8&selectedIndex=2&ccid=6YcuchdV&simid=608016466325015193&thid=OIP.Me9872e72175587a067af16f0b2f83282o0&ajaxhist=0) answer a question? If that was indeed a drive shaft failure, and he had more altitude, say a couple of hundred feet, would he have been able to perform an autorotation? Was the biggest problem here his lack of altitude while making his approach and it all went wrong at the worst time?
To get an idea that some combinations of speed and altitude make for a difficult ending, take a look at H-V diagrams. Here's a sample one, each helicopter will have variations on that same general theme ...

[FH1100 Pilot]

Do not assume that the apparent change in tail rotor RPM is because it is slowing down. Perhaps it is speeding up? The 206 produces a very distinctive tail rotor growl. Listening to the audio portion of that clip, it appears - at least to me - that the tail rotor is increasing in RPM. The video itself shows the nose yaw to the left. The helicopter drops like a rock.

These three things persuade me that it was an input drive shaft failure (the one that goes from the engine to the transmission). 206 drivers know that when you lose this drive shaft the engine is now powering the tail rotor, not the transmission. We are told that the N2 governor will hold the engine rpm at 100%, and that may be so. But I'd still bet that there are some RPM excursions while the governor plays catch-up.

An IDS failure would account for the apparent speed-up of the tail rotor, the left yaw of the nose, and the sudden, violent vertical descent.

To answer Rob Melvini's question... Yes, if the pilot had more altitude he certainly could have autorotated to a safe landing. But having all that beating and banging going on back there would have been disconcerting to say the least! In such an emergency, 206 pilots are cautioned to not roll the throttle off; doing so would remove power to the tail rotor, giving you yet another emergency on the way down! (I wonder if Bell has rectified this peculiarity with the 505?) But as one with "more than a couple" hours in 206's, even I would be sorely tempted to impulsively roll it off, and in my highly-stressed state of mind I might do just that.

[Paul Cantrell]

My reaction was "what a strange way for the helicopter to behave". Even assuming an engine failure, I would expect a collective pull at the bottom to greatly reduce the sink rate which made me think that one of two things was going on:

1) Something aerodynamic like VRS was causing a sink rate .... or
2) RPM was already very low and there wasn't much left to pull.

So, I did some counting of RPM. In the early part of the video we see the rotor taking 7 frames to make a main rotor revolution. Later, as the sink rate dramatically increases it's taking 10 to 11 frames for the rotor to make a revolution. That works out as:

(f/r = video frames per revolution)
(sec/rev = seconds/revolution)

7 f/r @ 30 fps = 0.23 sec/rev = 257 RPM = 65% Nr
10 f/r @ 30 fps = 0.33 sec/rev = 180 RPM = 46% Nr
11 f/r @ 30 fps = 0.36 sec/rev = 163 RPM = 40% Nr

So, by the time the video starts, he's already below the recommended touchdown RPM (70%). Most of his pull is already used up (and remember that energy in this case is a squared function of rotor RPM so there's not much energy in decelerating the rotor from 65% to 40%).

So, seeing that the rotor speed is that low, the video makes a lot of sense. He's had some kind of a power train failure (engine, short shaft) and at the time we first see it, he's already bled most of his RPM (early flare and pull, or hasn't lowered the collective enough to maintain flight rpm). Given all that, it's not surprising that we're seeing a dramatic acceleration towards the ground. By 40% Nr, the main rotor is providing little lift and gravity kicks in with a vengeance.

Happy to hear from you if I'd made any errors in my calculations...

[nigelh]

VRS etc is nonsense ! Also I don't see TRF either as your instinct would be to pull pitch ( which didn't happen .......or IF it did the blades were already about to stall ) coupled with the fact there was no serious yaw to left , 30 deg at most .
I think it was possibly a slow reduction of power /drive to the blades with subsequent rotor decay . Probably lucky to not reach the land and the tourists also thank God it was doors off . Let's hope the kid is going to be ok .
My money is governor failure .

[megan]

Reported as being five on board, including a 15-year-old boy who was taken to the hospital in critical condition. He had been trapped in the wreckage, and cut free by bystanders. A 50-year-old man and a 45-year-old woman also were treated at the scene by Honolulu Emergency Medical Services and taken to the hospital in stable condition.

My money is on drive failure.

[Max Power 3503e]

VRS.......

[no_one]

Paul Cantrell,

If your numbers are right, and I expect they are, then i think that the actual mechanical failure, what ever it was, occurred before the start of the video. Look at the google maps link I posted previously to where the accident occurred. There isnt a helipad near by but a largeish green park that is part of the pearl harbor monument national park.

If the pilot had engine failure at height before the video started, auto rotated to the park but then saw all obstacles/people and tried to arrest the decent and ran out of options.

[BOBAKAT]

My 2 cent : Freewheel failure

Why ?

1 / it's a normal approach =no VRS or other
2 /you listen clearly engine runing all the time = no engine failure,
3 / you listen clearly engine overspeed...It's mean, no more power transmitted to the rotor and T/R but engine runing
4 / The helicopter fall down like a block of concrete during a normal appproach = no power transmitted to the main rotor AND no reaction from the pilot (no time to react !)
5 / the briefly yaw is not due to an engine failure, but overspeed of the T/R

All of that = = no more free wheel runing ! it's a know defect on the 206


But, i was not on board.....

[parabellum]

Don't be misled by the apparent main rotor speed, it does look slow but that may be a factor of camera shutter speed.

[John Eacott]

I mentioned in posts No's 7 & 9 that it appears to be an approach to a precautionary landing at a suitable open space. This would indicate (as I mentioned) an existing fault indication and the freewhel fits this scenario, whereas a drive shaft failure is very unlikely to have given any prior indication.

Again putting on my Monday morning umpire's hat, I would have set up a far steeper approach to allow for the possibility of it turning into an auto with only the landing area as a suitable destination. It happened to me once (compressor failure on short finals to a floating pontoon) and I make the point long and loud to anyone who will listen: a steep approach is the only guard against losing power on short final that will assure a landing at the planned site for a single engine helicopter.



Rotor flicker/speed on a smartphone video is totally unreliable. Search for videos of stationary blades in flight, what you see on the video is unlikely to have any similarity to what actually happened.

[havick]

John are you suggesting to disregard the HV chart in the RFM?

Of course there are obstacle/wind/terrain considerations that necessitate a steep approach for operational purposes in some instances, however I think Bell would disagree with your technique of flying well and truly in the shaded section of the HV chart for just about every approach.

** only talking about single engine aircraft here.

[thepross]

Turning into a really boring thread by wannaabees. How about something went wrong and since i didn't have floats i was in the wrong place at the same time.... S..T happens.

[Arnie Madsen]

.

I am just making guesses like everyone else and I keep leaning toward VRS because how else could it drop so fast .

VRS could also explain the rpm increase because of unloaded blades and unloaded engine during the VRS

As far as I can tell MR pitch was never reduced ... so if it was a shaft or sprague failure a 206 should have mushed down as MRRPM decayed , not the sudden drop we saw.

.

[havick]

Turning into a really boring thread by wannaabees. How about something went wrong and since i didn't have floats i was in the wrong place at the same time.... S..T happens.

Pretty much sums it up perfectly.

[John Eacott]

John are you suggesting to disregard the HV chart in the RFM?

Of course there are obstacle/wind/terrain considerations that necessitate a steep approach for operational purposes in some instances, however I think Bell would disagree with your technique of flying well and truly in the shaded section of the HV chart for just about every approach.

** only talking about single engine aircraft here.

Please tell me where I have advocated disregarding the HV chart?

I recommended a steep approach such that a failure would leave the option of a successful autorotation, which is perfectly manageable within the recommended HV in the JetRanger Flight Manual.

That the approach chosen was too shallow is apparent from the flight path after the failure. Dragging a helicopter in to a landing spot on the backside of the power curve severely limits your options when Something Nasty Happens.

[ersa]

Don't worry John, Havic seems to attack your posts for some reason

[BOBAKAT]

I am from another school.....
For me, Steep approach mean lot of power available AND when you begin your speed reduction to land, your are "High", no power applied and very vulerable if anything happen.
Per sample : if the freewheel goes wrong at this time...your are ****** .

But i use it, i teach it, but only when needed

But i say it again, it's another school...:)

[VeeAny]

Chaps,

All this talk of HV curves, surely nothing to prohibit entry to the HV curve unless local operating regulations prevent you from being in it.

The conditions the HV diagrams are built for are not those usually met on the approach, steep approaches provided an appropriate technique is used for the aircraft type may well be absolutely fine. Avoid going into the curve for departure but not necessarily on the approach (for commercial operations where I am from any way).

Some of the larger types have the HV curve in the limitations section at which point they must be respected.

Gary

[Paul Cantrell]

John Eacott said:
Rotor flicker/speed on a smartphone video is totally unreliable. Search for videos of stationary blades in flight, what you see on the video is unlikely to have any similarity to what actually happened.

John, don't know if you were responding to my post about counting video frames or just responding to some of the people eyeballing it at full speed. You're certainly right that there are plenty of videos out there where the camera rate was close enough to the rotor RPM to cause illusions like stopped rotor systems.

In fact, that actually happens with the TR in this video: you can see that it appears stopped at first, the rotates slowly backward, and rotates slowly forward, etc. However you can tell that even when it appears to be moving backward that it is actually turning forward because the bottom blade appears bent forward due to the scanout of the video sensor.

Also, unlike the main rotor, the tail rotor is turning at a rate that is a multiple of the video capture speed. (2550 * 65% = 27 revolutions per second, very close to the 30 frames per second the capture unit was likely using. A 206 main rotor blade is turning at 6.5 revolutions per second at 100% Nr so this is unlikely to be aliased with any modern cell phone or video camera IMHO (with two blades you would be seeing 13 blades per second so if you were capturing at 15 frames per second you might get aliasing but I don't think any modern cell phone is capturing at that rate unless it's someone trying to capture at 4K, and you can easily tell 15 fps capture from the jerkiness of the video - note that lots of the "stopped MR" videos are 4 bladed where you're getting a 4x multiplier in the # of blades passing per second)

In any case, although the TR is showing these sorts of things in this video, the main rotor is turning slowly enough you can clearly watch the blade go round and round without it showing these sorts of video artifacts.


Then Arnie Madsen said:

I am just making guesses like everyone else and I keep leaning toward VRS because how else could it drop so fast .

VRS could also explain the rpm increase because of unloaded blades and unloaded engine during the VRS

As far as I can tell MR pitch was never reduced ... so if it was a shaft or sprague failure a 206 should have mushed down as MRRPM decayed , not the sudden drop we saw.


That's what I was saying at first, it seemed weird to see the helicopter accelerate towards the surface when we would all expect a slow increase in vertical speed, like watching someone do a hovering auto. But when you realize he had only 65% Nr at the beginning of the video, it actually fits quite well. For whatever reason, he ran out of RPM fairly high up and the acceleration towards the surface was just gravity doing it's thing. We all expect to see a mush towards the ground because we're expecting flight RPM, but in this case he was already almost unpowered at the beginning of the video. Therefore I don't think it was anything like VRS - I think it was a classic case of running out of RPM because of loss of power.

Normally this is the part where I would lecture everybody about the importance of maintaining Nr right until impact "if you're gonna crash, crash with lots of RPM to pull right before impact". We had a bad fatal accident here in Boston a number of years back where a low time State Police pilot apparently stalled the rotor after an engine failure, the result being that they fell at the end of the sequence and were all killed. I immediately thought about that accident when I saw this video, but in reading people's comments I'm thinking there is a chance this was a deliberate decision on the part of the pilot:

A couple of people have mentioned that it was probably an emergency landing where he realized at the last second there were too many bystanders to make the landing where he planned and he ran out of options. That sounds pretty likely. Putting it right at the edge of the water certainly maximizes the chances of the water being shallow enabling everybody to get out of the aircraft (rather than mid channel, say). Maybe he used his RPM to get right next to the shore, rather than preserve it for a soft touchdown further from shore. A tough decision and one that I hope I don't have to ever make.

I'm hoping the pilot will be interviewed soon and and we'll get a first person account of exactly what was going on.

[Junkflyer]

No civilians land in the Pearl Harbor area on purpose. Joint Base Pearl Harbor Hickam is right next to Honlulu International Airport and typically the last area a tour flies over before returning to land.

[Niner Lima Charlie]

The pilot said, "Tower, Chopper 8. I think I'm going down."

https://www.youtube.com/watch?v=MCKLRFOj-B4&feature=youtu.be

MCKLRFOj-B4

[oleary]

... and I make the point long and loud to anyone who will listen: a steep approach is the only guard against losing power on short final that will assure a landing at the planned site for a single engine helicopter.

Did we somehow share the same Irish ancestry way back when?

[oleary]

John are you suggesting to disregard the HV chart in the RFM?

Of course there are obstacle/wind/terrain considerations that necessitate a steep approach for operational purposes in some instances, however I think Bell would disagree with your technique of flying well and truly in the shaded section of the HV chart for just about every approach.

We observed the HV chart (mostly) when flying IFR offshore but a good part of my 18K R/W career was spent solidly in the HV curve.

I would also note that many Canadian training pilots will cheerfully put a 55/58/204/206/205/500 in a 150' hover and wack the engine.

That said, if you do not need to increase risk - don't - fly outside the HV curve.

[FH1100 Pilot]

BOBAKAT:I am from another school.....
For me, Steep approach mean lot of power available AND when you begin your speed reduction to land, your are "High", no power applied and very vulerable if anything happen.
Per sample : if the freewheel goes wrong at this time...your are ****** .

Bobakat, I'm not exactly sure what you are getting at here. I don't know what you're teaching, but if *my* freewheeling unit or input drive shaft (or engine, or tail rotor) fails, I'd rather be steep with a little airspeed than shallow and slow. Autorotations (and by extension flat-pitch approaches) have been demonstrated in every certified helicopter at maximum gross weight. It does not take Chuck Aaron to perform this maneuver.

As it was lifted out of the water, the blades of the Hawaii 206 look absolutely undamaged, meaning that they were certainly not under power and turning very slowly when they hit the water. Considering that we hear the tail rotor turning at 100% rpm or perhaps more all the way through the descent, it indicates a disconnect between the main and tail rotors. *Something* very mechanically bad happened to that helicopter.

[BOBAKAT]

@ FH1100 pilot

Sorry, i say again, we are helicopter pilot both, but not from the same "school". And i don't say you are wrong....i just explain some fact :

In europe (my school) :

Normal approach in Europe mean a slope between 3 and 5 °

For the FAA it's a "shallow approach".

For the FAA , the normal approach is under 13° .

"European Steep approach" begin above 5°
But is named "normal approach" By the FAA.

For the FAA, only above 13° slope it is a "Steep Approach.....


For me, to perform a steep approach and to maintain an acceptable rate of descent around 150 ft/mn, we reduce the speed at 2/3 of the normal speed approach.

For the FAA pilot, in "steep approach" they accept to have the rate of descent exceeding most of the time 300ft/mn.

I try the 2 method and i feel safer with "european Approach". Again, i don't say "you are wrong", i say, we are different...

Many post about "Settling with power" are posted by FAA pilot..... Why ? Easy, It is written in the FAA manual :

Steep Approach
A steep approach is used primarily when there are obstacles
in the approach path that are too high to allow a normal
approach. A steep approach permits entry into most confined
areas and is sometimes used to avoid areas of turbulence
around a pinnacle. An approach angle of approximately 13°
to 15° is considered a steep approach. [Figure 10-4] Caution
must be exercised to avoid the parameters for settling with
power

I drove for years on the right side of the road. Now for 10 years, i drive left side .... Nothing is wrong, just i moved from europe to Asia.

About the 206 crash, i explain just my opinion, but i say again : "i was not on board when the crash happened".
And maybe the T/R noise overspeed you are listen is the overspeed of the turbine runing free of charge ?
And sure, without free wheel, no more trust on the main and T/R. The blade of the T/R are destroyed ? As we see : no ...as the main rotor, for me they runing with a low speed at the impact..

And i am very surprised by the last audio posted there : the accident happen very quick on the vidéo and the pilot got the time to call the control and say : "i fall down" ?

[corey137]

The steep approach helps keep you in a safer position IF the engine quits on short final, but try steep slow approaches during summer in the mountains and you WILL have a lot of helicopters with pancaked skids.
But every approach is different, different locations, density altitudes, weights, etc. So there is never one perfect approach, the situation dictates what works best.

[Max Power 3503e]

What? Like coming to a hover at 500 ft agl in a Jet Box and then decending straight down?

[corey137]

"What? Like coming to a hover at 500 ft agl in a Jet Box and then decending straight down?"

Sometimes yes, with a 150' line and 100ft. timber, I'll often do a 300' vertical descent in a 206B.

But at max gross with an internal load at high DA I'm making a smooth, shallow approach to the LZ, hard to arrest a fast descent rate in that scenario with a steep approach.

[Gordy]

But at max gross with an internal load at high DA I'm making a smooth, shallow approach to the LZ, hard to arrest a fast descent rate in that scenario with a steep approach.

You might not want to do that...... I ALWAYS do a steep approach at high altitude unless you are doing a running landing or have a dedicated spot to set down.

[megan]

I recommended a steep approach such that a failure would leave the option of a successful autorotation, which is perfectly manageable within the recommended HV in the JetRanger Flight Manual.On three occasions that I've had engine difficulties followed your steep approach methodology John. Basically a power on auto, if the power is available at the bottom, good, if not, you get to complete a real auto. On the first two occasion it wasn't available, on the third it was.That the approach chosen was too shallow is apparent from the flight path after the failure. Dragging a helicopter in to a landing spot on the backside of the power curve severely limits your options when Something Nasty Happens. Regarding his low approach, perhaps he had reason to think pending MGB failure, and wanted to keep it low John. You may remember the Wessex that went into the water off Golden Beach. Kept it low due unusual high freq, and ultimately the MGB spat a gear out the side of the case, and removed a cyclic jack in the process. Aircraft rolled inverted at their 60' cruise height and entered the water. We rescued them with a fixed float 205 by landing on the water and pulling the survivors aboard.

[Max Power 3503e]

But at max gross with an internal load at high DA I'm making a smooth, shallow approach to the LZ, hard to arrest a fast descent rate in that scenario with a steep approach.

I rest my case...

[Gordy]

hard to arrest a fast descent rate in that scenario with a steep approach.

Why are you doing it with a "fast descent rate"?

It should be accomplished slowly, less than 200 ft/min descent rate and a slow walking pace forward with full In Ground Effect Hover power before you get below the demarcation line or before you descend below your "fly away point".

[Arm out the window]

I mentioned in posts No's 7 & 9 that it appears to be an approach to a precautionary landing at a suitable open space.

I'm with you, John - if the aircraft has been displaying symptoms of a possible problem (not sure if this was the case but likely from what has been previously said) then I'd go for a power terminated auto profile to a suitable open space, room and situation permitting.

Obviously might not be doable all the time, and WIRES may well be a factor if you don't have time to check properly, but all things being equal it's going to give you auto potential all the way down if power or drive are lost.

[FH1100 Pilot]

Maybe this is a little off-topic. It's funny that some pilots assume that a steep approach is necessarily a steep and fast approach. This is not the case. I flew a 206B for a rich guy - mainly out of his hunting camp and various dealerships that he owned. The sites we used were ALWAYS confined and we were ALWAYS heavy, both going in and coming out. There was no such thing as a "nice, gentle, shallow approach" to any of these places. The approaches often went beyond the FAA definition of "steep." Forty-five degrees was not uncommon.

You learn how to do it - learn how to ride the ETL burble all the way down. The 206 is great in this regard: Hold a cabin attitude that is just a degree or two below the horizon. As you come down into ground effect, simply raise the nose to the hover attitude (2 or 3 degrees above the horizon). Voila! The ship stops with hardly any power change at all. Very rewarding when done right.

Shallow approaches are for airplanes. In a helicopter I'll always take a steep approach over a shallow one. It might not always guarantee that I'll hit my intended spot if the engine quits, but I believe it's better than doing what the Hawaii 206 did.

[Gordy]

You learn how to do it - learn how to ride the ETL burble all the way down. The 206 is great in this regard: Hold a cabin attitude that is just a degree or two below the horizon. As you come down into ground effect, simply raise the nose to the hover attitude (2 or 3 degrees above the horizon). Voila! The ship stops with hardly any power change at all. Very rewarding when done right.

Spot on...... Here is how I do it, it lends for a very steep approach in excess of 60 degree angle:

1. Set up for a steep approach to be 100 feet above the obstacle in front of you.... for the sake of explanation we will call this the "decision point". You would aim to arrive at the decision point in a deceleration to little to no airspeed and less than 200fpm descent and almost hover power.

2. Just as you reach the decision point, assuming you have made the approach smoothly, you will push the nose over slightly to stop the deceleration and you will feel a little drop..raise the collective a tad to stop the drop and note your pedal position, TQ and TOT.

3. From those numbers you need the following to hover IGE:

a. An extra ONE inch of left pedal
b. An extra 5% TQ
c. An extra 35 degrees TOT

4. From those numbers you need the following to hover OGE.

a. An extra one and half inch of left pedal
b. An extra 15% TQ
c. An extra 50 degrees of TOT

5. Therefore, if when you were add the extra pedal you are at the stop, or if when you add the extra TQ or TOT to what you have already and it puts you in the red....you are in a position right now to pull power gently and nose over slowly to regain airspeed and fly away. I have used these numbers in the Jetranger, the L4 and a 407 and they all work.

6. If you have the pedal, TQ and TOT available, you continue the approach by letting the aircraft gently work its way down. As you approach the ground, raise the nose slightly and you will either come to a 1 foot hover or the skids will “kiss” the ground and then raise up again as the aircraft settles onto the ground cushion.

[Viper 7]

Gordy,

Very cool - a missed approach point for a high/hot/heavy confined.

Reminds me of the mountain crse in Penticton with Bill Foote, thanks for that!

[John Eacott]

Don't worry John, Havic seems to attack your posts for some reason

It's all those B412 hours with nothing else to think about ;)

I'm intrigued by the thread drift of late, and the reinforcement of my comment about setting up a steep approach when needed to improve your chance of making the spot. Those who have interpreted this to a vertical 500ft descent, or every approach to every landing, have missed the point. If you are guaranteed a safe forced landing area from 2 miles out for the duration of your approach then take a fixed wing PAPI glideslope by all means.

But if you have a possible emergency (as seems probable here) or are landing at a restricted site with no clear area in the undershoot, eg a floating pontoon, then go for a glideslope that will assure that you reach your destination even when it all goes quiet on short finals.

And Gordy has eloquently described the procedure for such an approach to a hot or high location, dispelling the idea mooted by some that you should be dragging in on a long, slow approach to a mountain landing :ok:

[Thomas coupling]

Meanwhile - what caused the crash!

[AnFI]

TC surface got in the way of the descent? ;)

[spinwing]

Mmmm ...

Good post John ... (and Gordy too :) ) ..

:E

[Max Power 3503e]

This fun trip for those pax and pilot, ended terribly...

[twinstar_ca]

ABC news is reporting the teen boy has succumbed to his injuries and that the family has donated his organs... Others will live because of this selfless gesture... Sincere condolences to the family and friends... :( :(

[Ricktye]

Watching the video of the ship coming out of the water by hoist, it doesn't appear there like there was little or no power to the main or tail rotors when it hit the drink. Looks like hardly any damage to them, as in they were close to stopped....

Condolences to all involved and affected!

[500guy]

"I think they were lucky that this happened over water"
Nay.


The skids bending absorb most of the G's on a vertical descent quite well. An inpact to water from the same altitude and level attitude has More G's on the occupants, not less.


Regarding the camera frame rate. I'm sure the video is compressed to be put online, likely lowering the frame rate. I'm not sure assuming 30FPS is reliable.

[FH1100 Pilot]

Ricktye:Watching the video of the ship coming out of the water by hoist, it doesn't appear there like there was little or no power to the main or tail rotors when it hit the drink. Looks like hardly any damage to them, as in they were close to stopped....

Rick, the main rotor blades are indeed undamaged. However in the pictures of the aircraft as it was recovered from the water, the tail rotor blades do look severely damaged.

Rumor now has it that it was the freewheeling unit that came apart, which would make a lot of sense.

[Arnie Madsen]

.

Watch the video at 25% speed and you can see the pilot kept it upright for a while after splashdown ... when the blades did start to hit the water they were still at max pitch and glanced back up in the air ... all of which slowed the blades right down before they went under.

.

[MikeNYC]

NTSB Prelim report is out:

http://www.ntsb.gov/_layouts/ntsb.aviation/brief.aspx?ev_id=20160218X71040&key=1

14 CFR Part 91: General Aviation
Accident occurred Thursday, February 18, 2016 in Honolulu, HI
Aircraft: BELL 206B, registration: N80918
Injuries: 1 Fatal, 3 Serious, 1 Minor.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.

On February 18, 2016, about 1020 Hawaiian standard time, a Bell 206B, N80918, was substantially damaged when it impacted water during an emergency landing near Honolulu, Hawaii. The helicopter was registered to a private individual and operated by Genesis Helicopters under provisions of Title 14 Code of Federal Regulations Part 91 as a local air tour flight. The commercial pilot and 2 passengers sustained serious injuries, 1 passenger sustained minor injuries, and 1 passenger was fatally injured. Visual meteorological conditions prevailed and a company flight plan was filed for the local flight. The flight originated from the Honolulu International Airport (HLN), Honolulu, about 0935.

The pilot reported to the National Transportation Safety Board (NTSB) investigator-in-charge, that while in cruise flight over Ford Island, he felt a vibration followed by a grinding noise. Shortly after, the pilot heard a loud bang, scanned the instrument panel and saw that the engine instruments indicated the engine was still running, however, rotor rpm decreasing. The pilot initiated an auto rotation to a grassy area near Contemplation Circle at the World War II Valor in the Pacific National Monument. As the pilot neared his intended landing area, he observed multiple people within the area. The pilot stated he initiated a left pedal turn, attempting to land close to the shoreline. Subsequently, the helicopter descended rapidly into the water, about 20 feet from the shoreline.

Witnesses located at various locations at the World War II Valor in the Pacific National Monument reported observing the helicopter near their location traveling at a low altitude before it suddenly descended into the water.

Examination of the accident site revealed that the helicopter was submerged in about 40 feet of water, about 20 feet from the shoreline. The helicopter was removed from the water the day following the accident and was subsequently rinsed with fresh water. All major structural components of the helicopter were recovered. The wreckage was moved to a secure location for further examination.

[RyRy]

Condolences to the family of the young man.
Hats off to the pilot for doing the best he could with a rotten situation.

[NutLoose]

Young lad named

Riley Dobson of Guelph, Ont. named as teen victim of Hawaii chopper crash | CTV News (http://www.ctvnews.ca/canada/riley-dobson-of-guelph-ont-named-as-teen-victim-of-hawaii-chopper-crash-1.2790935)

[megan]

he felt a vibration followed by a grinding noise. Shortly after, the pilot heard a loud bang, scanned the instrument panel and saw that the engine instruments indicated the engine was still running, however, rotor rpm decreasingThat'll upset all the VRS proponents (idiots).Turning into a really boring thread by wannabesYou have to wonder why those with absolutely no expertise find it necessary to jump in.

[LRP]

Final Report is out, no surprises.


http://dms.ntsb.gov/pubdms/search/dockList.cfm?mKey=92743

[gulliBell]

So what is the short story...Forward coupling of ET driveshaft had no grease or teletemps and failed due overheating and mechanical self destruction? A pilot wouldn't know there was no grease in the coupling (unless the seal was leaking), but would/should know as part of pre-flight inspection that the teletemps were missing. And with no teletemps on the coupling the aircraft should have been grounded for further investigation. Right?

[lelebebbel]

Sounds like the pilot should've been asking questions long before this flight. Expired straps, reused hardware when installing parts, no documentation, half filled out logbooks, negative component times on the paperwork...

... as a relatively inexperienced pilot, I guess he possibly didn't know any better - or if he did, he still would've been hard pressed to walk away from a turbine job.

I hope the new pilots reading this report can learn something from that.

[Ascend Charlie]

A pilot wouldn't know there was no grease in the coupling

Your preflight inspection should include running your fingers around the rubber boot, checking for splits or grease.

I found one in '97 that was split in such a fashion, with attendant grease spattering around the Txmsn well, that needed a driveshaft change. Another good reason for always wiping any grease or mess with a rag during the preflight, because any new stuff will show up in the postflight.

[gulliBell]

Your preflight inspection should include running your fingers around the rubber boot, checking for splits or grease.


Yeah, but the absence of any grease at all in the coupling, even if the seal was stuffed, would not yield any clue to the pilot that there was no grease in the coupling. Meaning the coupling was assembled without any grease. Hard to believe I know, but it wouldn't be the first time (I've seen a B212 ET drive shaft fitted without any grease in the coupling, it lasted for only the post-maintenance ground run before it turned kamikaze on itself).

[gulliBell]

... as a relatively inexperienced pilot, I guess he possibly didn't know any better - or if he did, he still would've been hard pressed to walk away from a turbine job.


I thought I read he was an ex-army Black Hawk pilot, so flying a B206 is probably a big step down from what he was used to.

[Hot and Hi]

Final Report is out, no surprises.


http://dms.ntsb.gov/pubdms/search/dockList.cfm?mKey=92743
This link brings me to a "docket". What is the link for the actual "Final Report"?

All I could find by searching the web was a "full narrative" https://www.ntsb.gov/news/press-releases/_layouts/ntsb.aviation/brief2.aspx?ev_id=20160218X71040&ntsbno=WPR16FA072&akey=1. No mention of Telatemp stickers in here though.

[vaqueroaero]

Try this.

NTSB Reveal Lax Maintenance Standards in Honolulu Helicopter Accident - Aerossurance (http://aerossurance.com/helicopters/lax-maintenance-honolulu-b206/)

[LRP]

This link brings me to a "docket". What is the link for the actual "Final Report"?

All I could find by searching the web was a "full narrative" https://www.ntsb.gov/news/press-releases/_layouts/ntsb.aviation/brief2.aspx?ev_id=20160218X71040&ntsbno=WPR16FA072&akey=1. No mention of Telatemp stickers in here though.


https://www.ntsb.gov/_layouts/ntsb.aviation/index.aspx

[Bitmonx]

MJB, no they don't fly low level. That video appears to show an unplanned approach to a precautionary landing at an open area.

Just to throw a bit more Monday morning umpiring into the equation: no floats on a Jettie carrying pax on extended overwater ops. Really?

John, if you do not know what you are talking about just keep your comments to yourself be it any day of the week.....

[John Eacott]

John, if you do not know what you are talking about just keep your comments to yourself be it any day of the week.....

Please tell me where there is anything in the first sentence that you quoted which has been proven incorrect? The second sentence was, as stated, a bit of Monday morning umpiring made two years ago.

Your superior knowledge in this matter is welcome if you have anything to contribute :ok:

[TWT]

This link brings me to a "docket". What is the link for the actual "Final Report"?This is all I could find. A 4 page summary.

https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20160218X71040&AKey=1&RType=Summary&IType=FA