slingsby firefly
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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?
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Robrob
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.
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.
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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.
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.
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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
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
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?
Or by "they" do you mean the USAF Academy?
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.
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.
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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:
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/slingsb...te_178534.html ]
The original T67A with the one piece canopy came with small rudders.
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.
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!
Is that incorrect?
[EDIT: And here: http://www.airteamimages.com/slingsb...te_178534.html ]
The original T67A with the one piece canopy came with small rudders.
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.
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'.....
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.
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'.....
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.
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
"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
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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.
Here's a link the NASA TDPF document: http://naca.central.cranfield.ac.uk/...ca-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.
he T67M-Mk2 variant was the first of the series used by the Royal Air Force for Elementary Flying Training.
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.
Last edited by robrob; 8th May 2016 at 12:21.
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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.
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.
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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
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
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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?
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?