slingsby firefly

[micromalc]

I fancy trying out a Slingsby Firefly. So far I've found 2 places that have them:
Cambridge & Thruxton.
Does anyone know of any others within 2 hours drive of London?
Thanks

[Foxy Loxy]

I think Stapleford have one, too.

Foxy

[rusty sparrow]

Two of 'em sitting on the grass there a couple of months ago - don't look like they've moved in months.

[mark147]

Cubair at Redhill have access to a T67MII.

[Miserlou]

Good choice.

I can give you the same briefing that I received. 'It's a very nice aeroplane. You will like it!'

[Foxy Loxy]

pboyall,

RAF Wyton do indeed have two, though you need to be a member of the flying club there. How easy it is to join I don't know. I can find out if you like.

Foxy

[micromalc]

contacted wyton....no go.....service personel only

[Foxy Loxy]

Hmmmm, had a feeling that was the case. Bad luck. There are restrictions on some of their flying activites, so it may not have suited you anyway.

Foxy

[Cusco]

Does anyone know of any others within 2 hours drive of London? Thanks
You should be able to drive to Cambridge in about 90 mins....................
I can do Cambridge-Gatwick in 1 hr 45
Cusco:rolleyes:

[pikanin]

A bit further from London - 2hours25mins on the train from York - Full Sutton east of York has one along with an acclaimed instructor.
http://www.pprune.org/forums/archive/index.php/t-147118.html
The above posts give some more detail.

[SNS3Guppy]

The USAF Academy flew them as part of a flight training program for the cadets. After a very thorough evaluation following three fatalities, they destroyed all the aircraft...wouldn't even allow them to be sold.

[Mikehotel152]

cjboy is correct as far as I know. Anyway, other nation's airforces use them as a primary trainer. Can't remember them off hand, but I'm sure a ppruner will come along soon with the details.

Stapleford have at least one. I did an hour aerobatics in it - fabulous fun. Mind you, compared with a Cessna 152, any low-wing, high-power aircraft would be! :O

[TractorBoy]

The last time I was at Stapleford, they were actually using the one from Cambridge - their own one was in the hanger being repaired - and apparently the one from Cambridge was rarely used, so Stapleford leased it. Best to check first if you're going to Cambridge !!

[eharding]

...wouldn't even allow them to be sold.


Because had they been sold, and then operated successfully in civilian hands, awkward questions might have been asked about why the USAF had a problem with them.....

[Mikehotel152]

They had the leased one and their normal G-BYOB at Stapleford last week.

[Merritt]

What's wrong with the one at Thruxton? Its my local airfield, takes me 45 mins from the M3/M25 interchange on an average day.

the a/c is active a fair bit...

Steve

[Merritt]

Just to add - when you get checked out on it (where ever it maybe).. Get the instructor to demonstrate its spinning capability ;)

[MikeJ]

cjboy,
Its you who should get facts straight. The US tests could not find fault, they put them back into service, and still continued to have problems.
Of real concern should be the civil UK experience. I know of a number of expert pilots who cannot fault the aircraft. BUT, in the UK, just in the last 6 years, 5 people have been killed in three accidents from non recovery from spins, from a height where this should not be a problem. In two of the cases, it was with an instructor who was conducting training.
All should read the AAIB reports - these are the facts.

[Merritt]

In my (very) limited flying experience, I have to say, I was totally shocked at how easily and quickly the firefly just flips in to a spin with the 'wrong' control inputs (spin training post PPL)..

[waldopepper42]

I used to fly the Slingsby, and went through a pretty comprehensive spin training exercise before flying solo aerobatics. I have also spoken to two very experienced Slingsby instructors (who teach spin recovery in the T67 almost on a daily basis) and both stated that if you apply the correct spin recovery controls and keep them applied - it WILL stop. Every time.

If you don't, it won't.

So, the moral seems to be, allow plenty of height for your practice aeros and get the proper training.

[snapper41]

Well, the RAF uses them:

http://www.raf.mod.uk/equipment/firefly.cfm

Probably not a bad recommendation!

[micromalc]

hi guys,
thanks for all the imput...looks like thruxton 4 me.
it seems to me that aircraft are just like everything else in life...use the right tool for the right job.
I"m into nice, gentle, graceful aeros and it seems that the firefly will do the job.
If i need anything more "exciting" i"ll try a YAK52.....thanks

[matspart3]

Tiger Airways at Gloucester have one. Googling will do the trick

[alvin-sfc]

So what would a typical hourly rate be?

[Merritt]

So what would a typical hourly rate be?

Thruxton charge 144.53 inc VAT, wet with instructor or £119.85 inc VAT wet without.

Steve

[Re-Heat]

Not bad value...!

[SNS3Guppy]

Guppy, get the facts straight. After a very thorough investigation, they could find nothing wrong with the aircraft. The decision to discontinue use was a political one, not backed by those in the know at the USAF.


I had a long discussion with one of the instructor pilots who had lost friends and two students in those crashes, and was head of the investigation team...and who was part of the decision to stop using the Firefly.

He certainly wouldn't agree with your position, which is incorrect. Then again, he was in a position to know.

[A and C]

I find your statment some what at odds with the findings of the UASF test pilots, who did a lot of testing after a number of these accidents happend.

Veiwing from this side of the Atlantic the political "not made in the USA" lobby seemed to have more to do with the USAF withdrawing the T67 from service that good opperational reasons.

The fact that in terms of value the aircraft was over 50% built in the USA seemed to have slipped the mind of those in power.

[Mikehotel152]

:uhoh:

Brown pants moment!

[SNS3Guppy]

I find your statment some what at odds with the findings of the UASF test pilots, who did a lot of testing after a number of these accidents happend.


You might, but the USAF didn't.

The aircraft which the T-3A replaced was the T-41 (several versions of the Cessna 172 XP), and it's purpose was the flight screening program; see if the applicant had any aptitude with a short introduction to flight.

The introduction of the firefly was also the introduction of an expanded program in which one obtained a private pilot certificate, and the training time was expanded from 40 hours to 50 hours. The T-41 was relegated to the Civil Air Patrol, a civillian branch of the USAF tasked with search and rescue, and to flying clubs at air bases around the country.

The USAF experienced 66 engine failures with the firefly, and grounded the fleet 10 times due to various problems. Half the fleet was flown at Hondo, TX, for initial pilot screening, and half at the US Air Force Academy (Colorado). Three fatalities occured at the USAFA. It was those fatalities, two cited as pilot error and one as unknown, the results of spins, which brought the program under scrutiny and eventually closed it. And no, it wasn't politics based on a British aircraft.

I will say that most people, myself included, thought the aircraft should never have been purchased.

In the 30 years of T-41 use preceeding the firefly, there had been NO fatalities.

Everybody who flew the airplane felt that it's general flight characteristics were fine. It was other things that they didn't like. Neither did the top brass, nor Congress. The program was a big waste of money, a fiasco. They should never have switched from the T-41.

[Carvair]

Mine at Sherburn is too far, but it's a delightful aircraft to fly - a real "stick & rudder" aeroplane. Fly one on the higher power models - the T67C, or any "M" version. Great aeros too!

[karl414ac]

There is a T67A at blackpool for hire on a no equity share scheme unsure of the prices as yet adn they have a good aero's instructer aswell

[Life's a Beech]

My CPL instructor was flying for EFT when the only UK military training Firefly crash happened. The instructor in that one admitted taking over too late when the student made the wrong recovery action (which worsens the spin in some way in the Firefly). He thinks it would have recovered without a problem, but standing orders to leave the aircraft at 3000 feet if still spinning, so they did.

Nothing wrong with the aircraft. Like any with decent performance it can bite you, and it was mishandled.

Guppy

The 172 is a docile machine to the point of tedium. Its handling is horrible, but safe, so it is no surprise there were no deaths. The surprise is that anyone learnt anything from it! A terrible training machine, worse than the 152, for anything but a future commercial pilot flying on instruments.

The T67 is an aerobatic aircraft. It was also possibly not well suited to flying over high terrain and with air conditioning (UK never fitted AC), so perhaps the procurement was not correct, but there was nothing fundamentally wrong with the design. Several military schools have had great success, and it is a popular aircraft at civvy clubs for increasing skills.

[robrob]

If you fly or plan to fly a Firefly you should read this: Aviation Safety Network list of T67/T-3 accidents (https://aviation-safety.net/wikibase/dblist.php?AcType=RF6). There's some interesting reading in those reports.

Keep in mind that pretty much every one of the dead Firefly pilots thought it was a safe airplane until just before impact so don't tell me, "I fly the T67 and it's a safe airplane." It's not. It's statistics are shockingly bad. It's got to be right up there with the F-104 Starfighter.

From a UK Fatal Stall or Spin Accident summary (1980-2008) report (http://www.gremline.com/index_files/page0053.htm):
The accident rate for the Slingsby T67 was throughout the period much greater than any other certified type and has been treated as a special case.

The Slingsby T67, (8 fatal accidents) was excluded from the main numerical analysis but was studied as a special case. (See Appendix 2 of the full Report).


Over 10% of every T67/T-3A has been destroyed in an accident and 35 souls have been lost to date (May 2016).

I flew the T-3A at the Air Force Academy and I call it the "Plastic Coffin."

[rotorfossil]

karl1414ac. I bought a share in a T67a and was very concerned when I investigated the complexities of the CofG considerations apart from the required low fuel loads for max weight for aeros. Because of the sliding seats, two long legged heavyish people put the CofG outside the the rear limits with possible spin recovery difficulties. My impression was that it was very important that the spin recovery was done in the right sequence, that is full rudder, pause, stick centrally forward. I also felt that some failures to recover were due to getting into an unrecognised inverted spin.

[robrob]

If the failure to recover was from an inverted spin they would have hit the ground inverted, right?

This is an interesting post I found Found on an online aviation forum archive:

---------------------------------------
Karl Bamforth
5th Jun 2009, 06:24

I remember an instructor and student getting into trouble trying to recover from a spin in a T67 in the UK.

Its a few years ago but when the Instructor told me what happened I could see how a student could get themselves into serious trouble. Thankfully both student and instructor survived the incident.

To the best of my fragile memory.
The instructor demonstrated a spin and recovery with no problems.
Handed control to student, the spin and recovery was normal until the "pull out from ensuing dive" part, they started to pull out of the dive but suddenly and violently departed and flicked hard into another spin.

The instructor took control and initiated recovery, once again the recovery was normal but in the later stages the aircraft once again flicked into another spin.

The instructor thought the problem was they were pulling too hard during the recovery causing the pitch angle to increase rapidly causing a further stall spin. On the last attempt he was much gentler in the recovery from the dive. The aircraft recovered normally.

Now if this had been a low houred pilot watching the ground getting ever closer and with a certain amount of panic setting in I think it would have ended in disaster.

Its the only first hand account I have come accross and it seems to fit the other failure to recover stories I have heard.
It certainly cured me of wanting to spin a T67.
--------------------------------------------

Because the T67/T3A spins so nose low the spin recovery is very nose low and it is common to pull the elevator too hard and get a secondary stall or buffet during the dive recovery. If there is any rudder displacement during a stall or buffet the T67/T3A will snap roll into a spin. If the rudder was rigged so the rudder was NOT neutral when the rudder pedals were neutral then it would be easy to encounter the behavior described in this post. Also, in the heat of the moment during the dive recovery it is easy to forget to neutralize the rudder or simply misalign your feet and leave enough rudder displacement to cause a snap roll spin.

[Genghis the Engineer]

An inverted spin is one where roll and yaw are opposite to each other. That means that it's upside down for a period of the time, but a snapshot moment may still find the aircraft upright, particularly if the mode is very oscillatory. That said, it's indeed most likely it would be inverted.

G

[robrob]

I did one inverted spin in the T-3A and it rolled right-side up upon entry and I thought it was over--that we didn't enter a spin. We then continued rolling and developed into a stabilized inverted spin. During the recovery with full anti-spin rudder I brought the stick from full forward to toward the rear and the aircraft popped out of the spin with just a little aft stick movement. The recovery dive was a pull from more than vertical so extra altitude, I would guess about 300 feet, was needed for the recovery. The lower rear of the rudder had a small puncture after the flight but we couldn't tell what could have caused the puncture damage.

Here is an interesting tidbit about the T67 and T-3A aircraft. T67's come with a small or large rudder. All the T-3A's came with the small rudder.

T67 with "Big Rudder"
https://robrobinette.com/images/T67_Big_Rudder.jpg

T67 with "Small Rudder"
https://robrobinette.com/images/T67M_Small_Rudder.jpg

T-3A with "Small Rudder
https://robrobinette.com/images/T-3A_Rudder.jpg

Note how bottom edge of the T67 "big rudder" (first photo) follows the angle of the bottom of the empennage and so has about two inches of rudder below the trailing edge position light. The T-3A on the right has a smaller rudder that angles up to the position light.

If we estimate the bottom length of the rudder to be 14 inches that gives us: (14 x 2) / 2 = 14 square inches. Fourteen square inches of additional rudder that's in the best possible location--mostly at the trailing edge below the elevator in clean airstream during a spin. If I owned a T67 with the small rudder I'd look into replacing it with the larger rudder.

I noticed the April 2016 spin crash T67 has a small T-3A style rudder.

https://robrobinette.com/images/T67_Slingsby_Firefly_Crash_2016.jpg

Another T67 fun fact:

Review of UK General Aviation Fatal Accidents 1985-1994

https://robrobinette.com/images/Review_of_General_Av_Accidents_UK_85_to_94.jpg

[abgd]

That makes a Firefly look a much better bet than a Pitts... If you compare like with like rather than comparing an aerobatic aircraft with something non-aerobatic.

[Jetscream 32]

robrob,

Healthy debate on a rumour forum is good but outright scaremongering is not really game!

small fin big fin is related the C or M model - BONSO was a C model and had the smaller rudder = standard and nothing wrong with it. The M model 260 has a larger fin as per the photo you present... You cannot put a M rudder on a C model!

You bleat on about the aircraft being unsafe...... actually what you are saying is that aircraft should never hurt anyone, and no one should pay any attention to the POH and pay no attention to weight and balance or any of the very very clear notes in the POH about aerobatics and in particular spinning.

The T67 is no different to the North American Harvard, bit of a handful when spinning and happy to flick and depart controlled flight, so don't self-teach yourself aerobatics - it will only end one way - unhappy!

The constant issue I have found when teaching spinning in the T67 of ALL variants is the students understanding the correct recovery technique and clear understanding that just because you have stopped the spin from entry direction you cannot simply just unload the stick a little bit and then start trying to recover from the inherent nose down attitude..... and large height loss, you have to UNSTALL the aircraft and let POSITIVE airspeed build, in the M model for a fully developed spin you can lose up to 800ft per turn allowing for recovery, don't go thinking you can nip up to 3000 and practice spinning in a T67 unless you do it every single day and are well within the CG limits..

Spinning a T67 should only be done ABOVE 5000 ft AGL (check density) and always wearing parachutes.... There is NOTHING wrong with the aircraft - its certified and there is nothing wrong with it.... Pilots of all abilities and experience often think they know best and maybe not pay attention to ALL information pertaining to the flight they are going to undertake... which occasionally then creates some sticky situations.

[Jetscream 32]

Also on a like for like basis the C182 has killed more per flying hour than the T67 - so I assume you are writing to Cessna also and trying to scaremonger them to pull the Type Cert are you?

[ak7274]

Whatever else you do, stay away from Pitts. The Cub doesn'the look too safe either. Don't you just love statistics?

[A and C]

As an American you should consider the views of one of your finest occupants of the White House who offered the opinion that " There are lies, damm lies and statistics "

On the numbers given if a shared your veiw I would be calling for the C182 & PA18 to be banned from flying.

The USAF flight test people at Edwards had the T67 doing 14 turn spins with no ill effects so I doubt it is the aircraft that is to blame, I think we need to look at the training of those flying it.

Most of the aircraft that are reguarly used for spinning in GA that don't just fall out of the spin like the C152 & G115 have a reputation ( DHC-1 & PA-38 ) for not recovering from spins. Mis-loading and poor understanding of recovery technique along with misunderstanding the increase in roll rate in the final part of the recovery are all likely to be reasons that an aircraft fails to recover.

[tmmorris]

Also the stats don't take account of the fact that the majority of those buying the T67 probably did so for aerobatics and/or spin training; whereas the C152s will rarely have been spun if ever. Much higher exposure to risky activities per hour.

Where are the stats for the Zlin? Grob 115/Tutor? A friend of mine (and A and C's) nearly had to abandon a Zlin which wouldn't recover from a spin for some time and turned out to be outside C of G limits.

[A and C]

Tim

I've only flown the Grob 115A and all you need to do to recover from the spin is let go of the controls, I expect the Tutor ( military G115 ) will exhibit a conventional spin recovery

[Cows getting bigger]

..... and now they operate the SR20?

[BossEyed]

Nope. The replacement EFT aircraft will be (it isn't yet) the Grob 120TP, a very different aircraft from the SR20 which was never considered for the role.

Or by "they" do you mean the USAF Academy?

[Cows getting bigger]

I'm on about the Americans. :ugh:

http://www.flyingmag.com/sites/flyingmag.com/files/styles/medium_1x_/public/import/2011/sites/all/files/_images/201107/Cirrus_T53A_Big.jpg?itok=SE2mO_t9

[BossEyed]

Bang your head at me all you like - the lack of clarity wasn't mine.

In any event, the role of the aircraft now at USAFA is not the same as when they had an aerobatic capable aircraft in the Firefly.

[robrob]

Jetscream, I'm curious as to why the T67M260 would have the big rudder and the T-3A with the same engine + air conditioning have the small. Any insight?

Jetscream_32 said:

small fin big fin is related the C or M model - BONSO was a C model and had the smaller rudder = standard and nothing wrong with it. The M model 260 has a larger fin as per the photo you present... You cannot put a M rudder on a C model!

G-BNSO is being reported as a T67M MKII here: https://aviation-safety.net/wikibase/wiki.php?id=186878

Is that incorrect?

[EDIT: And here: http://www.airteamimages.com/slingsby-t-67-firefly_G-BNSO_-private_178534.html ]

http://www.fullsuttonairfield.co.uk/wp-content/uploads/2013/03/G-BNSO-Slingsby-T67-Firefly.jpg

The original T67A with the one piece canopy came with small rudders.

http://www.airteamimages.com/pics/76/76110_big.jpg

Does anyone know when and why Slingsby began building the large rudder Fireflies? From my photo search-->registration search, all the big rudder aircraft are T67M260's but some M260's have small rudders. It seems all the T67M MKII have the small T-3A style rudders.

I believe the real problem with the US Air Force T-3A's was that it was chosen as an initial trainer for student pilots with zero flight time. The original plan was to allow students to solo in the pattern and to the training areas. I think most of us recognize how absurd that plan was for the T67M MKII/T-3A. Luckily the AF came to their senses before we started sending students with 14 hours of total flight time out to the areas solo in an aerobatic aircraft without parachutes.

The stall & spin characteristics of the T67M are not suitable for an initial trainer. All four of the T-3A's destroyed were stall and spin related. The first was an intentional spin without recovery. The second was a bounced landing stall at Hondo Airfield. The third was an engine out gliding stall into a spin. The fourth was a climbing engine failure to stall to spin.

[BEagle]

All of which indicates that poor instructor training was the most probable cause...

I've read a lot of total and utter nonsense written about the Firefly - including 'The (US) Air Force didn't practise glide stalls' and 'It wouldn't recover by releasing the controls'.....:mad:

Any aeroplane will kill idiots; sadly, the USAF seems to have proved it.

Of course for the ambulance-chasing bloodsuckers, it's easier to allege that the aeroplane was at fault, rather than inadequate training, mishandling and late take over of control by the instructor.

I didn't like the T-67A due to its abysmal roll rate and lack of V-P prop, which made aerobatics a pain compared to the Bulldog. But I had absolutely no qualms about the spinning behaviour, provided that the fuel loading was carefully observed and the correct recovery technique used.

[Genghis the Engineer]

A few relevant thoughts.

"Lies damned lies and statistics" is Benjamin Disraeli, who never occupied the Whitehouse. It was popularised in the USA by Mark Twain, who didn't occupy the White House either. I think that Disraeli was talking about Florence Nightingale who pioneered the use of statistics to explain stuff to bewildered politicians (did you know she also invented the pie chart).

There are much more up to date statistics than 1994 available.

I think that anybody flying club aeros without a chute and/or too low for further recovery actions or to abandon is a fool. Clubs permitting this are being irresponsible. There are clubs doing so in common types, including the T67. I have no idea if this includes Yorkshire Aero Club.

Rudder area below the horizontal stabiliser is based upon a 1930s piece of RAE research, developed further in the 1950s by NASA called "Tail Damping Power Factor". NASA themselves revisited it in the 1970s and published a report saying that it was misleading and should not be used. Brunel University in the UK a few years ago also revisited it, concluded the same, and published similar papers in Aeronautical Journal.

You would expect aeroplanes used extensively for aerobatics to have a significantly higher fatal accident rate anyhow. That doesn't however explain the 1994 statistics for the C182 and Jodel.

T67M Mk.II is a non-military 160hp variant. M200 and M260 are the models actually sold to the world's military forces.

G

[robrob]

Rudder area below the horizontal stabiliser is based upon a 1930s piece of RAE research, developed further in the 1950s by NASA called "Tail Damping Power Factor". NASA themselves revisited it in the 1970s and published a report saying that it was misleading and should not be used. Brunel University in the UK a few years ago also revisited it, concluded the same, and published similar papers in Aeronautical Journal.

The problem found with TDPF was using it against the aircraft "inertia yawing moment" in a simple equation. "Unshielded rudder volume" (area not blocked from the airstream by the horizontal stabilizer) is still very important to effective spin recovery. It doesn't take an aeronautical engineer to understand that having extra rudder in clear air would help slow a spinning aircraft.

Here's a link the NASA TDPF document: http://naca.central.cranfield.ac.uk/reports/1946/naca-tn-1045.pdf

67M Mk.II is a non-military 160hp variant. M200 and M260 are the models actually sold to the world's military forces.

From the Slingsby Owners' Club website:
he T67M-Mk2 variant was the first of the series used by the Royal Air Force for Elementary Flying Training.

The Canadian RAF flew the T67C.

I'm still trying to figure out all the T67 models. Could you guys look this over and see if you agree?

Specific question, where is the T67M200 fuel tank(s) located? Firewall or wings?

T67 Firefly Models

T67A 1981 O-235 4 cylinder 118hp engine, copy of RF-6B, made of wood, 2 blade fixed prop, fuel in firewall tank, single piece canopy, 10 built

T67B 1984 O-235 4 cylinder 118hp engine, made of glass reinforced plastic as are all models below, 2 blade fixed prop, fuel in firewall tank, single piece canopy, 6 built

T67M 1983 AEIO-320 fuel injected 4 cylinder 160hp engine, 2 blade constant speed prop, fuel in firewall tank, inverted flight systems, single piece canopy, 32 built (32 includes the T67M MKII)

T67M MKII 1985 with AEIO-320 fuel injected 4 cylinder 160hp engine, 2 blade constant speed prop, fuel in wing tanks, inverted flight systems, 2 piece canopy

T67C 1987 with O-320 4 cylinder 160hp engine, 2 blade constant speed prop, non-inverted systems, fuel in firewall tank, single piece canopy, 28 built. Some T67C's were built with two piece canopies and wing fuel tanks. The Canadian RAF flew the T67C3 with 2 piece canopies and wing fuel tanks.

T67M200 1987 with AEIO-360-A1E fuel injected 4 cylinder 200hp engine, 3 blade constant speed prop, fuel tanks located ?, inverted flight systems, 26 built

T67M260 1993 with AEIO-540-D4A5 fuel injected 6 cylinder 260hp engine, 3 blade constant speed prop, fuel in wing tanks, inverted flight systems, 51 built

T67M260-T3A 1993 with IO-540-D4A5 fuel injected 6 cylinder 260hp engine, 3 blade constant speed prop, fuel in wings, inverted flight systems, air conditioning, all had "small" rudder, 114 built and sold to US Air Force. Four were destroyed in accidents, Edwards flight test kept one, the rest were scrapped.

[SFCC]

T67A. 10 built, very few left.
0-235 engine, wooden airframe. Fuel tank forward of panel.

Nice enough aeroplane, only as aerobatic as an RF4. Given its designer, not entirely surprising.

[Hueymeister]

Turweston near Silverstone have one.

[robrob]

Thanks for the corrections, I edited the above list. I also changed the T67M200 to the AEIO-360 with 200hp.

[50+Ray]

Just want to add a few facts to the conjecture.....
GBNSO was one of the 5 second hand Fireflies bought by Huntings when they got the initial JEFTS contract. This reduced the average cost of the fleet. It had the T67M 160 hp two bladed prop they all had, but was given a red spinner on Red Nose Day one year and always known as Bonzo.
The T67M200 had the Bulldog engine, 200hp and a three bladed prop. Barkston had two - G HONG and G KONG, no guesses where they came from. They really did not perform much better than the 160s, and frankly the prop/engine match up was not great. Weight and CofG had to be watched for spinning & aeros.
The T67M260 was by far the best example, and I also flew it for 9 years in Bahrain where naturally it had an air conditioner.
The accident at Barkston has been described elsewhere. Mis-handled recovery, late takeover by QFI and jump out at Min Ht. All crews always wore Parachutes!
An extra 1000 feet was added to the calculations for safe recovery and the school had no further problems.
I did not know these unfortunate students. I do not know how much training or time on type they had, but over the years many competent pilots have suffered when not familiar, not in practise, and not following a drill precisely to the letter. RIP
The Jordanians have also had fatal accidents in their Fireflies. One aircraft struck a bus at LL. To my knowledge the machine was not at fault

[robrob]

The T-3A had no center of gravity maneuver limitations and we never considered it--at all--but we flew with some big football player students, two parachutes and full tanks and would take off and go directly to the area (about 10-15 minutes flight time) and begin spinning. We were told that one or two pilots with any fuel level would always be within CG limits.

Because the entire fleet was new, none of the T-3's had been measured (put on scales) since they left the factory. I asked our maintainers about the weight and balance measurement procedure but no one knew how to level the plane for the measurement. I knew the aircraft's measurement datum line and how to calculate the moments but I needed to know how to level the plane for an accurate measurement. Typically the procedure is to place a level on the cockpit floor or storage compartment floor. I contacted Hondo's maintenance chief and he said he didn't know how to do it since the procedure hadn't been needed yet. I even contacted Slingsby but could not get an answer. I got the feeling they didn't want us to look into the CG issue too closely.

I decided to weigh the aircraft anyway. I put a T-3 on the scales with full wing tanks and oil, plus me and a cadet in the seats with our parachutes on with the canopy closed--exactly the situation for a normal takeoff. The aircraft was scaled inside a hangar with a known level floor. The weights at all three wheels were taken and the numbers crunched. We were over two inches rear of the rear CG limit! I tried to push this info up the chain of command but because the aircraft wasn't leveled to Slingsby's specification (whatever that was) no one believed the numbers. I know that leveling the aircraft will move the CG but there's no way it was going to shift the CG two inches forward--you'd have to stand the aircraft on it's freakin' nose to do that. The bottom line is we were flying the aircraft with an extremely aft center of gravity and no one wanted to admit it.

As wing fuel burned off the aircraft's CG would shift forward so the T-3A would become more stable throughout the flight. It's worth noting the first accident aircraft took off, went directly out to the maneuver area, flew one maneuver--most likely a "spin prevent" (recovery of incipient spin), climbed up to 11,700 feet and entered the fatal spin with nearly full fuel tanks and an aft CG.

Could someone post the maneuvering CG limits for the T67? Are they the same for all the variants?

[Cows getting bigger]

robrob, reading your story I can't help but think that those who procured and brought the T-3A into USAF service had a lot to answer for.

[Baikonour]

For those interested, here (https://dl.dropboxusercontent.com/u/33669257/94P%20SPIN%20TEST%20Slingsby%20T-3A.pdf) is a USAF document about spin tests they carried out on the Firefly.

B.

[Jetscream 32]

robrob,

Cant help but read into your posts that you never had sight of the POH handbook - you are stating some incredible failures in operating a military aircraft across all levels of responsibility and accountability...I'm sure you might be paraphrasing but if as you are writing that is how they operated the aircraft it is no wonder the USAF had the incidents they had.!
Not wishing to be disrespectful!

[dobbin1]

Could someone post the maneuvering CG limits for the T67? Are they the same for all the variants?

The CG limits for our T67M MkII (160hp version) can be obtained here:-

Slingsby SR Group (http://gbnsr.org.uk/)

No idea if these limits are the same for the bigger engined varients, but I doubt it.

[robrob]

Jetscream, the Air Force had its own self-written operating and maintenance manuals. The pilots studied the flight manual and knew it inside and out. But as mind boggling as it sounds we did nothing for weight and balance--it was never considered or calculated. The other glaring omission is that we never practiced gliding stalls and we never received any "student screws up the spin recovery" training. We got that training on the job and it was eye opening.

I do believe that we were operating the aircraft with the CG beyond the aft limit which would make the aircraft more unstable and more likely to enter and remain in a spin.

dobbin1, thank you for the excellent link. I'm looking at the weight and balance spreadsheet and reading through the manual now.
Baikonour, thanks for the link to the spin testing document. I didn't know the spin testing was carried out at Hondo Texas.

The more I learn about the T67 the more I realize the Air Force did a crappy job of developing the operating manual and the training syllabus for the instructors and the cadets.

[sapperkenno]

The more I learn about the T67 the more I realize the Air Force did a crappy job of developing the operating manual and the training syllabus for the instructors and the cadets.

So maybe a change to your website, and every previous post you've made on the subject blaming the Firefly is on the horizon? :confused: You're entitled to your opinions, but it's a shame the T-3a never worked out... I can't help thinking if it had been an American design, all the problems would have been ironed out in time and you would have had yourselves a fantastic training airplane.

[BossEyed]

I do believe that we were operating the aircraft with the CG beyond the aft limit which would make the aircraft more unstable and more likely to enter and remain in a spin.

Well, that would hardly seem to be an issue with the aircraft - whatever its design or origin - then.

[robrob]

For those interested this document is a great review of the T67M260 and the Air Force's Enhanced Flight Screening Program's development: https://fas.org/man/dod-101/sys/ac/docs/t3bar.pdf

The Air Force tested the T67M200 in August 90 and tested the brand new T67M260 in August 91.

The report mentions some fatal accidents that aren't listed in the ASN database:

1984 UK Aerobatics "Aerial display; insufficient altitude for maneuver"

1985 UK Spin accident resulting in two fatalities from a "failure to recover." The 1986 Cranfield crash is also mentioned so it's not that crash.

1987 Sweden Aerobatics "Low level aerobatics" It lists the Switzerland spin accident so it not that crash.

1989 Japan "Steep turn after takeoff , rolled inverted."

1989 Turkey Simulated Forced Landing "Wing dropped near the ground."

1989 Turkey Formation "On inside of turn after takeoff, hit house."

1990 New Zealand Aerobatics "No information"

Adding these fatal accidents to the ASN T67 database (https://aviation-safety.net/wikibase/dblist.php?AcType=RF6) gives a total of 28 fatal T67 accidents.

Anyone have any info on these unlisted fatal accidents?

sapperkenno, I have updated my T-3A webpage but the T67 still has a god awful safety record. Over 10% of the T67 fleet have been destroyed in fatal accidents.

Well, that would hardly seem to be an issue with the aircraft - whatever its design or origin - then.

It doesn't explain the other 25 fatal crashes all over the world. How about the Test Pilot Instructor that "failed to recover" from a spin in Mojave California? You can't write that one off on "some dim-wit that doesn't know how to do a proper spin recovery."

[The Ancient Geek]

Simple - A low level spin in ANY aircraft is unlikely to be recoverable.
Spin recovery needs a lot of altitude. Only a suicidal idiot would enter a deliberate spin below 5000ft AGL.

[sapperkenno]

Only a suicidal idiot would enter a deliberate spin below 5000ft AGL.
How many T67s have spun in doing competition aeros? Top of the box wouldn't be more than 3500' agl. Granted they're not intending to do more than a couple of turns, but still.

[Camargue]

Ancient greek - 1 1/2 turn competition spins are done from 3000-3500ft, (well that's the aim, entry may end up being in the high 2000's) often with a high rotation element so that thde exit is vertical. the trick is to do it in a plane designed for proper aerobatics, unlike say a slingsby or bulldog. Of course at that height a 'chute is probably not going to help much. I'm sure though slingsby's have been flown in many competitions

[dobbin1]

A 1 turn competition spin in the T67m uses around 1100 ft so spinning from 3000 or 3500 is not a problem if you know what you are doing.

If I am spinning with a student on the controls I always start above 5,000 ft just in case they get the recovery wrong. We always wear parachutes and practice abandon drills on the ground as part of the AOPA aeros course.

In the 10 years I have been flying and teaching aeros in the T67 I have never got into an accidental spin (plenty of departures of course, but always recovered at incipient stage by centering the controls) and I have never had any hint of a problem recovering from fully developed intentional spins. Always aware that the next one might be the first problem one though.

[Jetscream 32]

In summary to 4 pages of pruning - I think we can safely say the T67 is a fine aircraft if you operate it as per the POH and within CG limits.
Always do an AOPA aeros course if you want to have $hits and giggles doing loops, rolls and other fun stuff.
Always wear a parachute
Don't self teach aeros
Simples!

[robrob]

My summary of 4 pages of pruning:

36 T67's destroyed with 48 fatalities in flying accidents. That's the new total using the ASN and Enhanced Flight Screening Broad Area Review report.

Know what you're getting into when you get into a T67.

[RatherBeFlying]

AFMs commonly give a single arm for the crew positions, even though seats are commonly on tracks.

Parachutes (or more importantly lack of) will also affect the arm.

Many of us single seat glider owners will have the glider CG calculated after weighing with pilot wearing chute and strapped in.

I bought my first glider from a gentleman weighing some thirty pounds more than me; so I had to remove several tail weights. The fellow who bought it from me reinstalled them.

Another consideration is that North Americans, including USAF personnel, tend to weigh more and be taller; so sitting farther back.

[dobbin1]

AFMs commonly give a single arm for the crew positions, even though seats are commonly on tracks.

Parachutes (or more importantly lack of) will also affect the arm.

Many of us single seat glider owners will have the glider CG calculated after weighing with pilot wearing chute and strapped in.

I bought my first glider from a gentleman weighing some thirty pounds more than me; so I had to remove several tail weights. The fellow who bought it from me reinstalled them.

Another consideration is that North Americans, including USAF personnel, tend to weigh more and be taller; so sitting farther back.

The seats in the Slingsby are fixed position. The rudder pedals are adjustable to allow for taller or shorter pilots, so I don't think the arm of the pilots will change with weight or size. Our w&b spreadsheet gives the option of wearing a parachute. Careful fuel planning is required if you want to fly with two fat blokes and parachutes.

[MikeeB]

Only a suicidal idiot would enter a deliberate spin below 5000ft AGL.
How many T67s have spun in doing competition aeros?

Top of the box wouldn't be more than 3500' agl. Granted they're not intending to do more than a couple of turns, but still.

I did, in BONZO. I normally started at 3500ft, the spin was always early in the sequences that I did during my short foray in to aerobatic competition, so 3000ft for entry, anything below and I'd can it, and did do. It's a few years since I've flown, but I do remember some wise words that came my way, "one day, you'll put in the inputs to recover the spin and it won't recover as you expect, don't start £$%"£$"£ about with it, stick with it and it will drop out" It did it once and completed another rotation and then dropped out. I don't know why, but it did. From memory the FF's are not cleared for inverted spinning, but I had instruction on how to recover from that as well, should it happen. I always flew with a chute just in case.

If/When time and money allows and the kids stop bleeding me dry, I'll start flying again, and I would quite happily fly a FF.

[robrob]

I believe there is duplication between the two reports you mention, so your total is wrong.

Did you compare the two lists? Tell me which ones you think are duplicates.

Is it this one from the BAR report?

1984 UK Aerobatics "Aerial display; insufficient altitude for maneuver"

From the ASN database:

1984 Slingsby T67M Firefly G-SFTY Specialist Flying Training Ltd 1 Torquhan Farm, near Galashiels - Cross country flight, pilot bailed out too low and died.

1985 Slingsby T.67A Firefly G-BJGH Specialist Flying Training Ltd 0 Teesside International Airport, Middleton St. George, County Durham - Nose wheel fell off, damaged beyond repair

1986 Slingsby T67M Firefly G-FFLY Slingsby Aviation PLC 1 Cranfield, Bedfordshire (EGTC) - This crash is in both reports and I accounted for this - not duplicated

1987 Slingsby T67A Firefly G-BIUZ Slingsby Aviation PLC (reg. owners) 0 Cranfield, Bedfordshire - Takeoff stall crash avoiding a midair, no fatality, written off

Here's a screen capture of the ASN T67 accident database:
https://robrobinette.com/images/T67_AviationSafetyNet_Accidents_May_2016.jpg

[robrob]

"one day, you'll put in the inputs to recover the spin and it won't recover as you expect, don't start £$%"£$"£ about with it, stick with it and it will drop out" It did it once and completed another rotation and then dropped out. I don't know why, but it did.

This is the key. That warning should be plaquered on the instrument panel. Sometimes the Firefly doesn't react the way it should.

It's like ghosts, you don't believe in them until you see one yourself.

Was this a right-hand spin? The Edwards test flight guys found the aircraft recovered quicker from left-hand spins. They speculated it was due to prop wash making the rudder more effective. The fatal Academy intentional spin crash hit the ground in a right-hand spin. The Apr 2016 crash looks to be right-hand too.

We should also take note that many of the T67 crashes resulted from stalls, some at low level, some that progressed into spins. In the T67 stall + rudder = aggressive wing drop. That should be plaquered too.

[Cows getting bigger]

This is the key. Sometimes the Firefly doesn't react the way it should.

That is the same with any aircraft if you find that little spot that no one else has experienced, hence my comments on a similar thread about spinning and parachutes.

[India Four Two]

From memory the FF's are not cleared for inverted spinning,MikeeB,

Read the very interesting report in Baikonour's post:
For those interested, here (https://dl.dropboxusercontent.com/u/33669257/94P%20SPIN%20TEST%20Slingsby%20T-3A.pdf) is a USAF document about spin tests they carried out on the Firefly. Here's the relevant part:
Inverted Mode Discovery
The possibility of an inverted spin seemed remote, due to the reluctance of the aircraft to depart or spin from an inverted stall. We tried roll coupled entries, but could not generate sufficient roll rate to translate to a yaw rate. The only card left unturned was the effect of the elevator trim (remember that trim tab)--could it make a difference?

We found with the elevator trim set full nose up, the aircraft would spin inverted in either direction. This was accomplished from an inverted stall, with full forward stick and full pro-spin rudder held throughout the incipient stage (1 to 2 turns) and the developed spin. The full nose up setting of the trim tab allowed an extra bit of elevator control power when inverted. This in turn, kept the angle of attack high enough to allow a yaw rate to develop. And as we know, stall plus yaw equals spin.

Follow-On Tests
Naturally, Slingsby wanted to further investigate the inverted spin mode. Their follow-on testing completed before delivery verified the importance of the trim tab for inverted spins. Expanding from the QT&E sorties, they looked at both forward and aft CG, as well as heavy and light aircraft weights. In all cases, once the trim was set more than half nose up, the propensity for inverted spinning increased. The aircraft was more susceptible to inverted spins with right rudder, though it could spin both directions once the trim was set to full nose up (as we had done during QT&E). Slingsby also found the neutral recovery to be most effective for the inverted spin. In the end, Slingsby recommended the aircraft not be certified in this area and for inverted spins to remain a "prohibited" maneuver. In part, this decision was an economic one, as travelling the certification highway can be a long and expensive journey. And on-time delivery of the aircraft was paramount to both the USAF and the contractor.This is a very interesting report and it merits reading completely. When I opened it, I had expected a typical, dull, factual USAF flight-test report. However, this is a very interesting, well-written paper, presumably presented at a conference. Does anyone have a reference?

I think the summary at the end of the paper is very telling:
Overall Assessment and Impact of Testing
On the USAF side, we were pleased with the Firefly's spin characteristics--how it spun when you wanted to and a when you weren't expecting it. The inverted spin potential seemed remote enough to eliminate most of the worry on part of the user. The T-3A had a no-nonsense, erect spin mode that would expose pilots to the spin environment in a safe and energy-efficient manner. As long as the pilot utilized rudder for primary anti-spin control, most mistakes during recovery could be tolerated.I've never flown a T-67, but it seems to me, to be not a lot different from the Chipmunk - apply the correct recovery procedure and it will always come out of a spin.

As an aside, but relevant to robrob's comment about W&B of the T-3A, when I flew Chipmunks at UBAS is the 60s, there was never any discussion of gross weight or W&B. I presume the assumption was that even with ex-truckie middle-aged QFIs in the back seat, there was no issue. ;)

[Gertrude the Wombat]

If/When time and money allows and the kids stop bleeding me dry, I'll start flying again
In my case it was thirteen years until the childcare budget dropped to zero and I could start flying again.

[MikeeB]

Great read, thanks. More than anything, that report explains the importance of following the spin recovery technique, or it isn't going to stop. It echo's what I was taught, but never with the context behind it.

The throttle part is interesting - it suggests an easy entry in to another spin in the opposite direction unless you are quick off the rudder. Also recovery from an inverted spin can be achieved by merely centralising the stick, not requiring opposite rudder and stick back.

I miss flying - I hope it's not thirteen years !!!!

[ModernDinosaur]

I do believe that we were operating the aircraft with the CG beyond the aft limit which would make the aircraft more unstable and more likely to enter and remain in a spin.
[...]
The more I learn about the T67 the more I realize the Air Force did a crappy job of developing the operating manual and the training syllabus for the instructors and the cadets.

Having once stalled my T67M Mk-II with the CofG at (but not beyond) the aft limit, I can confirm that the behaviour is MASSIVELY different to even a few millimeters further forward, and I will not be repeating the experiment. I would not want to spin the aircraft with an aft CofG, but I am quite happy spinning it elsewhere in the W&B/CofG envelope.

Sadly the "crappy job" robrob refers to resulted in multiple fatal accidents and wrecked the reputation of a very capable aerobatic initial trainer aircraft.

In my opinion, the Firefly's biggest weakness is that it is too easy to fly (and to aerobat) most of the time, imbuing pilots with confidence not matched by their competence. This results in them taking risks they don't understand and aren't capable of handling, giving an accident rate which is higher than some other aircraft, but it is lower than others, and is comparable with most other aerobatic types which are used primarily for aerobatics (i.e. discounting the C152Aerobat which is seldom aerobatted).

[dobbin1]

Having once stalled my T67M Mk-II with the CofG at (but not beyond) the aft limit, I can confirm that the behaviour is MASSIVELY different to even a few millimeters further forward, and I will not be repeating the experiment. I would not want to spin the aircraft with an aft CofG, but I am quite happy spinning it elsewhere in the W&B/CofG envelope.

Sadly the "crappy job" robrob refers to resulted in multiple fatal accidents and wrecked the reputation of a very capable aerobatic initial trainer aircraft.

In my opinion, the Firefly's biggest weakness is that it is too easy to fly (and to aerobat) most of the time, imbuing pilots with confidence not matched by their competence. This results in them taking risks they don't understand and aren't capable of handling, giving an accident rate which is higher than some other aircraft, but it is lower than others, and is comparable with most other aerobatic types which are used primarily for aerobatics (i.e. discounting the C152Aerobat which is seldom aerobatted).

I'm curious. In what way was the spin behaviour different with the aft CofG?

[PFA flyer]

I did some spin training in a T67 with 160hp and a fixed pitch prop where I believe we were within the CG limits. On one upright spin to the left I put in full right rudder and was then in the pause before moving the stick forward but before I did that the spin 'instantly' changed to one to the right. I was thinking to put in left rudder but my instructor very quickly took control and recovered, I guess he wanted no delay. So the lesson learned was to neutralise the rudder as soon as the rotation stopped and perhaps be a little quicker moving the stick forward.

I now fly a Pitts and there have been cases of people being in an upright spin in one direction crossing over to an inverted spin in the other direction whilst trying to recover and being unable to recognise the change before crashing. So again the lesson learned is to neutralise the rudder as soon as the rotation stops and perhaps be NOT so quick in moving the stick forward.

It seems all types have their peculiarities in the spin, at least in the Pitts the Mueller/Beggs method works when you are unsure what to do.