T-28 crash Hungary airshow

[Mike_dublin]

A PLANE CRASHED during an air show in Hungary today, leaving two people dead and four injured, officials said. A video in local media showed the plane – a 1951 North American Aviation T–28 Trojan, according to media reports – tumbling from the sky and exploding on the ground.

Hungarian news site with a number of pictures (https://www.feol.hu/helyi-kek-hirek/2023/09/lezuhant-egy-sportrepulo-a-fehervari-repulonapon-video)

https://www.feol.hu/helyi-kek-hirek/2023/09/lezuhant-egy-sportrepulo-a-fehervari-repulonapon-video

[sablatnic]

Not as much tumbling as looking to me like panic attack during a low altitude slow roll.

Link to video: https://www.youtube.com/watch?v=T8AcTEsFSoM

[sycamore]

Simple `Rule1` for rolling manoeuvres in airshows; Roll axis`always above,seldom level,never below..the horizon`.

[treadigraph]

Simple `Rule1` for rolling manoeuvres in airshows; Roll axis`always above,seldom level,never below..the horizon`.
Can't remember who said it (Lecomber?) but also start the roll towards the crowd line (as happened here) so if things go awry during the second half, an anxious pull takes the accident away from the spectators. It seems the impact was in a car park and those injured were in a car.

[fdr]

As much fun as the T28B was to own and fly, it was not a great aerobatic aircraft, but it was a great trainer of the use of trim. teaching someone else to do aeros could end up with a demonstration of falling out of a roll from being crossed up. Was a blast but much more work than a Pitts. Much like a T6. Rolling with altitude to recover from a mess was nice to have. Sad end to the old girl, and those involved. The B had a fair bit more get up and go and could shuffle along quite nicely.

[markkal]

As much fun as the T28B was to own and fly, it was not a great aerobatic aircraft, but it was a great trainer of the use of trim. teaching someone else to do aeros could end up with a demonstration of falling out of a roll from being crossed up. Was a blast but much more work than a Pitts. Much like a T6. Rolling with altitude to recover from a mess was nice to have. Sad end to the old girl, and those involved. The B had a fair bit more get up and go and could shuffle along quite nicely.


The first half of the barrel roll was executed correctly, starting with the nose above the horizon to avoid negative g's once inverted with constant roll rate.

Something went wrong after the first 200-250 degrees or so of rotation. Il looks like he stopped rolling , as trim was most likely set for straight and level 1g, once past inverted failing to complete the roll the nose at 1g positive would point straight to the ground; The movie clip seems to confim this.

Easy to comment from my armchair at home, but again as the first part of the roll was technically correct and at a safe heigh compatible with the roll rate if not interrupted.
Something went wrong which I cannot logically explain..
My respects to those invoved.

[GeeRam]

Can't remember who said it (Lecomber?) but also start the roll towards the crowd line (as happened here) so if things go awry during the second half, an anxious pull takes the accident away from the spectators. It seems the impact was in a car park and those injured were in a car.

By the looks of this video taken from outside airfield, car hit was parked off in a field likely as off site viewing of the show.

https://www.youtube.com/shorts/oTMM_MO1J2E?feature=share

:eek: (https://www.youtube.com/shorts/oTMM_MO1J2E?feature=share)

[Vessbot]

The first half of the barrel roll was executed correctly, starting with the nose above the horizon to avoid negative g's once inverted with constant roll rate.

Something went wrong after the first 200-250 degrees or so of rotation.

There isn't a clear reference in the video so it takes some mental extrapolation (as well as Monday morning quarterbacking) but I'm seeing it different: somewhere between zero and 10 degrees of pitch up. Haven't flown a T-28 but if it's anything like the T-6 (heavy on the controls, low roll rate) and if I'm seeing it right, then that's not nearly sufficient, and it was wrong before any amount of rotation.

[treadigraph]

By the looks of this video taken from outside airfield, car hit was parked off in a field likely as off site viewing of the show.

Indeed...

There isn't a clear reference in the video so it takes some mental extrapolation (as well as Monday morning quarterbacking) but I'm seeing it different: somewhere between zero and 10 degrees of pitch up. Haven't flown a T-28 but if it's anything like the T-6 (heavy on the controls, low roll rate) and if I'm seeing it right, then that's not nearly sufficient, and it was wrong before any amount of rotation.

Looks like some pitch up into a slow roll to me in the vid posted by GeeRam, whole thing went awry while inverted. Seen a couple of other videos which show him rolling the day before (right rather than left if memory serves), somewhat faster. Not a barrel roll, not to start with anyway.

[markkal]

Indeed...



Looks like some pitch up into a slow roll to me in the vid posted by GeeRam, whole thing went awry while inverted. Seen a couple of other videos which show him rolling the day before (right rather than left if memory serves), somewhat faster. Not a barrel roll, not to start with anyway.


Thanks for the other video showing it from another perspective.
I fly regularly high performance aerobatic aircraft of the last generation which I own one. I concur these warbirds are heavy with a slow roll rate.

But roll rate depends on speed; The aircraft buzzed at quite high speed ( probably as it often happens he dived from altitude and gained a fair amount of speed before passing the crowd line).

would estimate it in excess of 350 km/h. And the roll rate as I see it is far from sluggish. Technically the first half of the roll is well executed, with correct inputs both from rudder and stick.

Then the nose started to dive and the rotation stopped. The rate of rotation and height both suggest the maneuver could have been completed safely. Something went clearly wrong

[DogTailRed2]

Control restriction caused by loose object in the cockpit? Wasn't that one of the suspected reasons for the P38 crash at Duxford?

[sablatnic]

Control restriction caused by loose object in the cockpit? Wasn't that one of the suspected reasons for the P38 crash at Duxford?

Heard about, I believe, a kneeboard.

[megan]

Haven't flown a T-28 but if it's anything like the T-6 (heavy on the controls, low roll rate)Did my training on the 28B and C with the USN, only have experience with the T-34 and Chipmunk to compare the handling and wouldn't put in the heavy category. Bob Hoover was the one who did the initial test flying on the aircraft, it was said the roll rate had to be reduced so as not to over whelm students, some of our instructors had a shares in a P-51 and said the 28 out performed the 51 with the exception of speed.

[fdr]

The first half of the barrel roll was executed correctly, starting with the nose above the horizon to avoid negative g's once inverted with constant roll rate.

Something went wrong after the first 200-250 degrees or so of rotation. Il looks like he stopped rolling , as trim was most likely set for straight and level 1g, once past inverted failing to complete the roll the nose at 1g positive would point straight to the ground; The movie clip seems to confim this.

Easy to comment from my armchair at home, but again as the first part of the roll was technically correct and at a safe heigh compatible with the roll rate if not interrupted.
Something went wrong which I cannot logically explain..
My respects to those invoved.

Think we have differing training on what a barrel roll is supposed to be vs a slow roll or hesitation roll that is fallen out of. If in competition the start of this would have been questioned as to what was intended.

The opportunity for FOD in the T-28 is pretty high, within the cockpit area and in the baggage compartment. Not as lethal as the Yak-52 in that resect, but still get a good collection of memorabilia when inverting.

Control restriction caused by loose object in the cockpit? Wasn't that one of the suspected reasons for the P38 crash at Duxford?

It may well be the cause.

Did my training on the 28B and C with the USN, only have experience with the T-34 and Chipmunk to compare the handling and wouldn't put in the heavy category. Bob Hoover was the one who did the initial test flying on the aircraft, it was said the roll rate had to be reduced so as not to over whelm students, some of our instructors had a shares in a P-51 and said the 28 out performed the 51 with the exception of speed.

My first flight in a T-28B was with Bob, the same day I went flying with Bob Love in his P-51, out of SJC, 47 years hence. Hard to pick between them as most enjoyable. Changing speed or power changes the forces markedly to keep pointing in the right direction on the T-28, you can still get the outcome but being near trim on all 3 axis makes it a lot smoother to fly. Starting one up is fun, a lot better with a Darton kit, and it always made one respect the process newbies went through when they walked out to those for their first flights.


https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1523x1523/t28_cockpit_in_flight_7f7a9e2692f787881d93e0768b469e3b1adbc4 15.jpeg
https://cimg0.ibsrv.net/gimg/pprune.org-vbulletin/2000x1504/13988168_141470709629568_1361227557616235034_o_fd7c20f9cc642 a5cc420c708b1081af3cefaa7e5.jpg

[megan]

fdr, heading for the Lexington.always made one respect the process newbies went through when they walked out to those for their first flightsStudents had about 22 hours, of which about 5 solo, in a T-34 before progressing to the T-28 where they went solo after about 10 hours. Always thought of the 28 as a 34 with a bit more power, handling similar.


https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/695x541/batc0001_ba5bfa438f3baf475ccf7d320a7b8fe0c9ee8c0e.jpg
https://cimg0.ibsrv.net/gimg/pprune.org-vbulletin/505x646/batc0009_a8b5ea50673868d938f2a99aca47daac7b4fb868.jpg
https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/711x574/batc0010_60e82a4535e9b1ecf067a11e4f98a6b53c5d3cb9.jpg

[markkal]

Heard about, I believe, a kneeboard.

Using a kneeboard or any other object when performing maneuvers is really not recommended, as well as carrying a passenger during airshows in the times I was doing them was prohibited. Not only it is a liability, but it adds weight.

[DaveReidUK]

Did my training on the 28B and C with the USN, only have experience with the T-34 and Chipmunk to compare the handling and wouldn't put in the heavy category. Bob Hoover was the one who did the initial test flying on the aircraft, it was said the roll rate had to be reduced so as not to over whelm students, some of our instructors had a shares in a P-51 and said the 28 out performed the 51 with the exception of speed.

The accident aircraft was a former Fennec, i.e. one of the ex-USAF T-28A's sold to the French AF and re-engined with the supercharged R-1820 (and armed), subsequently transferred to the Argentine Navy and then later on the US, Canadian, South African, Swiss and (finally) Hungarian registers.

[treadigraph]

Heard about, I believe, a kneeboard.

Kneeboard and a multi-tool found loose in the wreckage of the P-38, no witness marks to confirm either caused a control restriction.

Re the T-28, suggestion elsewhere that the roll might have been an eight-point hesitation; videos certainly do give a slight impression of quick stop-starts.

[markkal]

Kneeboard and a multi-tool found loose in the wreckage of the P-38, no witness marks to confirm either caused a control restriction.

Re the T-28, suggestion elsewhere that the roll might have been an eight-point hesitation; videos certainly do give a slight impression of quick stop-starts.


On the first video filmed by the crowd line, the roll is not a hesitation one - no 1/8th or 1/4th stops., it's constant roll from what I can see, the fist 180 degrees of the maneuver is very clean and properly executed.
I can clearly see the dive before passing the crowdline which suggests -As if often happens during airshows- that there has been a dive to gain airspeed, to be in the safe side and increase roll rate.

Then there is a shallow climb, very shallow indeed in case of an aircraft which may not have inverted oil and fuel systems, to anticipate the rolling. However american radial engines normally have pressure carburettors, with mechanical fuel pumps replacing carb floaters and jets and if so equipped. Negative G's would not interrupt flow, let alone for that brief moment if the carb was a standard one..

I stress on the "shallow" climb attitude at the roll start and the cosequent flat attitude when inverted which requires more forward stick to unload and pehaps a brief passage in the -1 G territory.
But the pilot showed high level of proficiency and coordination. Roll rate is appropriate as well as height above the ground to complete such maneuver That is what is puzzling me, how he went from such precise flying to what looked like a sloppy and sudden interruption in roll and consequent nose drop if trimmed for +1g cruise flight.

We have a very smooth precise trajectory and roll until past 180 then it degenerates
Something does not add up here.

Tool kit or loose kneyboard may have played a role.

[GeeRam]

There isn't a clear reference in the video so it takes some mental extrapolation (as well as Monday morning quarterbacking) but I'm seeing it different: somewhere between zero and 10 degrees of pitch up. Haven't flown a T-28 but if it's anything like the T-6 (heavy on the controls, low roll rate) and if I'm seeing it right, then that's not nearly sufficient, and it was wrong before any amount of rotation.

Yep, ex-Marine pilot on another forum reckoned a min of 20deg pitch up required.
He said, he's been backseating in a 28 during practice at altitude with an airforce pilot doing the same thing, and an only 5deg pitch up saw a 800ft altitude loss as a result.....

[markkal]

Yep, ex-Marine pilot on another forum reckoned a min of 20deg pitch up required.

He said, he's been backseating in a 28 during practice at altitude with an airforce pilot doing the same thing, and an only 5deg pitch up saw a 800ft altitude loss as a result.....


Starting the roll with 5 degrees pitchup if he did not sustain in pitch (With forward stick to unload) while inverted definitely altitude loss is a factor to consider

However the more I look at the video the more it looks like past inverted around 200 to 220 degrees into the maneuver there is an interruption in roll which i deem to be main contributing factor followed by a pull on the yoke until impact.


There is zero error margin when performing aerobatic maneuvers at low altitude.

[markkal]

Here we have a clip showing same aircraft and same pilot doing the same maneuver before properly executed throughout, at the same height with very little bank nose up at the outset practically on axis.
So both pilot and aircraft were capable of such a maneuver.

https://www.facebook.com/SzegedTV/videos/1493286841469016

https://www.facebook.com/SzegedTV/videos/1493286841469016 (https://www.facebook.com/SzegedTV/videos/1493286841469016)

[212man]

I'm intrigued by the brief roll reversal just before impact

[treadigraph]

I'm intrigued by the brief roll reversal just before impact
High speed stall perhaps?

T-6 will flick the other way if pulled hard enough in a turn I believe - saw it occur high over Arundel once from underneath, steep left hand turn getting tighter, sudden snap into a steep right turn, I imagine probably a demo by instructor.

[Vessbot]

I'm intrigued by the brief roll reversal just before impact
I see no such thing?

[sablatnic]

I see no such thing?

It is there, very shortly before the crash, best seen in this "video": https://www.youtube.com/shorts/oTMM_MO1J2E

[Vessbot]

It is there, very shortly before the crash, best seen in this "video": https://www.youtube.com/shorts/oTMM_MO1J2E
Oof... yikes. Yeah, accelerated stall while they're pulling for dear life certainly explains it.

[First_Principal]

I'm intrigued by the brief roll reversal just before impact

I'd wondered about that too. Given what subsequently occurred my thought was that perhaps, selflessly, the pilot had spotted their trajectory could hit someone on the ground and attempted to manoeuvre away in the last few seconds.

FP.

[markkal]

Oof... yikes. Yeah, accelerated stall while they're pulling for dear life certainly explains it.


Definitely dynamic stall, a reflex to pull hard on the stick to get away from approaching ground.

[IFMU]

Definitely dynamic stall, a reflex to pull hard on the stick to get away from approaching ground.
That was my thought as well. It seemed like the maneuver could have been completed if not for that pull while inverted. Started off small but then some panic when it was apparent there was no recovery.

[sycamore]

Roll rate on pull-up was about 36*/sec,; roll rate from inverted,nose below horizon was only about 24*/sec;;the only recovery from the highest point,about 550`agl was a brisk roll,and no pull...

`Zero Error Margin` is a book written by Col. Des Barker SAAF about 20 yrs ago,which goes into all about Airshows/Air Displays...It is difficult to find copies,but can be downloaded off Google...

[Pilot DAR]

Some more thread drift today....

`Zero Error Margin` is a book written by Col. Des Barker SAAF about 20 yrs ago,which goes into all about Airshows/Air Displays...It is difficult to find copies,but can be downloaded off Google...

I attended a flight test session presented by Des a number of years ago, the theme being: You're the company test pilot, they're going to tell you to demonstrate the plane at an airshow, these are some things you should know..... An excellent presentation! Des occasionally flew a unique GA type in South Africa, which was quite similar to the plane I own, we had quite a chat about it. Sadly, he was killed flying it a few years back.

[markkal]

Roll rate on pull-up was about 36*/sec,; roll rate from inverted,nose below horizon was only about 24*/sec;;the only recovery from the highest point,about 550`agl was a brisk roll,and no pull...

`Zero Error Margin` is a book written by Col. Des Barker SAAF about 20 yrs ago,which goes into all about Airshows/Air Displays...It is difficult to find copies,but can be downloaded off Google...

Great book, It deserves to be read !!!!

[blind pew]

Is it conceivable that he pushed forward too much inverted and approached an inverted stall?
i ask this as I’ve found myself inverted on three occasions when the aircraft didn’t do what I expected.
My first was in a Victor air tourer out of Sunderland in the 70s attempting to demonstration to my brother a loop and the aircraft descended on its back which I only managed to exit with rudder and aileron.(my 5 hours aerobatic training on a chipmunk reverted to forced landings as my instructor was petrified teaching Aeros).
My second was my first attempt at a slow roll from 1,000ft in a glider when the roll rate reduced to zero. Realising that I was in a stable inverted stall from pushing too hard I converted to the last half of a loop, conscious that there might be a conflict with VNE and having been told that to avoid that pull hard to destroy energy I pulled with the G meter pegged at 6.
My third was in a Grob teaching the french art of mountain soaring on a slope with an escape route out of the Cape gliding club adjacent to the local quarry when a loud bang found us inverted at 200ft whilst flying figures of eight in lift surges. Recovery was stick neutral..allow nose to drop, speed to build and roll out.
of course I could be writing twaddle

[wub]

Is it conceivable that he pushed forward too much inverted and approached an inverted stall?
i ask this as I’ve found myself inverted on three occasions when the aircraft didn’t do what I expected.
My first was in a Victor air tourer out of Sunderland in the 70s attempting to demonstration to my brother a loop and the aircraft descended on its back which I only managed to exit with rudder and aileron.(my 5 hours aerobatic training on a chipmunk reverted to forced landings as my instructor was petrified teaching Aeros).
My second was my first attempt at a slow roll from 1,000ft in a glider when the roll rate reduced to zero. Realising that I was in a stable inverted stall from pushing too hard I converted to the last half of a loop, conscious that there might be a conflict with VNE and having been told that to avoid that pull hard to destroy energy I pulled with the G meter pegged at 6.
My third was in a Grob teaching the french art of mountain soaring on a slope with an escape route out of the Cape gliding club adjacent to the local quarry when a loud bang found us inverted at 200ft whilst flying figures of eight in lift surges. Recovery was stick neutral..allow nose to drop, speed to build and roll out.
of course I could be writing twaddle

I don't think I fancy flying with you.

[fdr]

Is it conceivable that he pushed forward too much inverted and approached an inverted stall?
i ask this as I’ve found myself inverted on three occasions when the aircraft didn’t do what I expected.
My first was in a Victor air tourer out of Sunderland in the 70s attempting to demonstration to my brother a loop and the aircraft descended on its back which I only managed to exit with rudder and aileron.(my 5 hours aerobatic training on a chipmunk reverted to forced landings as my instructor was petrified teaching Aeros).
My second was my first attempt at a slow roll from 1,000ft in a glider when the roll rate reduced to zero. Realising that I was in a stable inverted stall from pushing too hard I converted to the last half of a loop, conscious that there might be a conflict with VNE and having been told that to avoid that pull hard to destroy energy I pulled with the G meter pegged at 6.
My third was in a Grob teaching the french art of mountain soaring on a slope with an escape route out of the Cape gliding club adjacent to the local quarry when a loud bang found us inverted at 200ft whilst flying figures of eight in lift surges. Recovery was stick neutral..allow nose to drop, speed to build and roll out.
of course I could be writing twaddle


nope. The images do not support a push inverted to the extent that a negative g stall would occur. The trajectory supports a low g case but not significantly negative, so, no stall at that point.