Aint disagreeing with anybody, but a passing comment.

In the event of an inadvertent spin, it follows (inevitably) a loss of control.

The RAF (rightly imho) teaches a loss of control drill (close throttle, centralise everything). Almost always, this will recover an aircraft from the departure, before a fully developed spin occurs, and with minimal loss of height.

Why then do most civil schools, and civil aircraft manuals, teach ONLY a fully developed spin recovery, which really needs at least a full turn (and probably 500ft height loss) before you can identify the mode after in inadvertent departure.

It strikes me that standard civil teaching, is potentially quite hazardous in the event of a low level loss of control? Opinions anybody?

G

Good points Genghis.

The business of training people to recover quickly and safely with minimum loss of height following an inadvertent loss of control or “departure from controlled flight” aka “departure” is a difficult one – and yet arguably the most important thing.

Ideally, the departee (how about that) will be with it enough to recognise what is happening as a departure, and simultaneously chop the throttle and put everything in the centre (and hold it there against possibly large control snatching). I agree that if that is done accurately and quickly then motion about any axes will likely stop and you then just have a recovery from an unusual attitude to do – ie roll wings level to the nearest horizon using aileron and then (and not before) ease out of the dive.

Personally I doubt that a departee who has not had the confidence building benefit of full standard spin entry and recovery training (to say nothing of aeros training) will react by executing this drill. I fear many will just instinctively oppose the aircraft motions – coarse use of aileron to counter the perceived bank angle and sick hard back to get the nose up. In which case, in the circuit, all is likely lost.

JF




[This message has been edited by John Farley (edited 08 September 2000).]

Good thread,
The recent canadian accident report and the accident I witnessed recently have knocjked my confidence in spinning just when I thought that I was comfortable (if anyone ever is!!) with it. A 150 with half tanks should always recover was what I was taught as an instructor, any other comments?

Keep it up chaps.

There seems to be little comment on the fact that the cc was not properly used to unstall the ac. I always understood, for standard recovery, full opposite rudder, pause, then STICK PROGRESSIVELY FORWARD UNTIL THE SPIN STOPS. In some ac (ie chippie) this CAN mean forward onto the stop.(no I havn't forgotten about throttle, aileron neutral etc. - just expect people to know those)

I'm keen to learn more about pecularities of the Bulldog spin from anyone who has first hand knowledge.

I've been teaching Aeros (in Bulldogs) at Old Sarum for several years. In that time the aircraft has never spun from manoeuvre (despite studes trying to perform various unnatural acts).
Deliberate competition style (1 or 1.5 turns)spinning has always been predictable with no oddities.
Teaching of deliberate academic spins or spins from deliberately botched manoeuvres has sometimes lead to brief excitement:
- Rudder reversed but stick held on back stop leads to agressive transition to high rotation in other direction (not surprising).
- Elevator relaxed during spin leads to high rotation and delayed recovery (also not surprising).

Has anyone seen anything else happen?
Although I haven't tried a deliberate inverted spin in the Bulldog I've been stalled inverted many times without any signs.

I'm one of many people who at various times got to spin the Bloodnot at Sunny Boscombe when it managed to scare a few more students or QFIs.

We always decided it was basically friendly, but did have a definite potential to frighten. I can't recall any tendency to spin of a manoeuvre either. The particular mode of rudder-induced high rote is new to me, but the elevator relaxation problem (or moving the stick forward too slowly during recovery) was a known characteristic.

The standard way to create a high rotational spin was about ½ in-spin aileron during the spin. The high rotational spin was always recoverable but could take a couple of turns, and never gave warning - you have to hold the recovery controls on until somebody belts you in the side of the head and you know it's recovered (often the lateral g on recovery tended to destroy vision for a couple seconds, which was entertaining).

If you've got the Lycoming inverted oil system mod fitted, the oil pressure drops to zero or thereabouts during the spin as well, which isn't inherently dangerous but bears keeping an eye on and can increase fuel consumption a bit.

We never felt the urge to try inverted spinning, so if you intend to try that you will be turning very quickly into a test pilot. Personally, I'd advise against it.

G

Thanks for all the posts. At 220 hours I did my first Mustang trip. The briefing included spinning with min entry height around 12,000. Recovery action had to be taken after not more than two turns. Average height loss in turns and during recovery was about 3500ft.

There was a warning that power-on entries should never be intentionlly performed. If you inadvertently left power on during the spin, the aircraft would not recover. It was nice to have a parachute as standard equipment. The Pilots Notes warned that once you closed the throttle after a power-on entry, you could expect up to five or six turns to occur after initial recovery action. Expected height loss was 10,000 ft.

I spun the Mustang without trepidation in those long gone days because if one had the altitude and did the right things, it would soon recover. The C150 can be a nasty little beast and it does concern me sometimes. Especially the news that a badly rigged wing could cause a serious spin problem. My experience with C150's is that wing rigging is often awry which means a nasty wing drop at stall. Regretfully, few pilots report this in the tech log which means the next pilot can be caught by surprise.

Back in time again, The RAAF lost a Winjeel and both pilots following an intentional spin. With no witnesses and no CVR, it was assumed that they had crashed in a spin simply because that was the exercise in the authorization book.

With the possibility that the crashed Winjeel was a rogue spinner, the RAAF had each Winjeel in the inventory tested by an RAF test pilot who was based at the Aircraft Test and Development Unit at Laverton.

Each aircraft was given 8 turns (left and right) before recovery action was initiated. Entry was from 8000 ft. I think about 30 Winjeels were tested and all were given a clean bill of health. It will never happen of course, but it would be interesting to see the results of similar spin test flights in the C150.

As a neo-natal Pitts pilot, I will read anything that is I feel may either contribute to my safety or longevity, hence following this thread...

I have just finished Fred DeLacerda's book Surviving Spins (ISBN 0-8138-0142-7).

His C150 research is based on 105 one-turn spins and 42 multi-turn spins totalling 281 turns using two different airframes.

In it he discusses the Muller-Beggs recovery technique but his research shows that the no-hands recovery will not work after 3 turns for A C150. He does go on to say that that it may work again after 5 but that piece of work was still outstanding, this was because of rotation rates stabilising.

He concludes the chapter by stating that the C150 is very predictable and will recover as advertised "PROVIDED the airplane is maintained and flown within manufacturer recommendations."

Nothing new there then.

Apparently Cessna in 1980 published a booklet
Spin Characteristics of Cessna Models 150,, A150, A152, 172, A172, & 177.

sNr

If you are interested in developing a deep understanding of spinning, I recommend the spinning chapter of Darrol Stinton's book "Flying Qualities and Flight Testing of the Aeroplane".

G

It's nice to see this topic being aired, as I feel that the concept of spinning in simple a/c is not always given the respect it deserves. I am particularly pleased to see the Bulldog being cited as I have some experience of its behaviour.

Although I only flew it as a student, I have about 150 hours on type and before leaving UAS was fortunate enough to fly low level aero's in competition in it. So, most of my time was GH with a lot of spinning practice.

The fatal accident referred to happened the year before I joined and resulted in a change of SOP; the parachute was not removed until the pilot was out of the a/c and standing on the ground. It was then placed back in the a/c. Previously it had been removed in-situi, hence the possible cognitive failure by the QFI leading to him falling from the harness.

The student who bailed out leaving his QFI in a cabriolet T MK1 was on the UAS that shared our airfield, and his caterpillar club tie was a good talking point in the bar!

I was once shown the high rotational mode by my QFI shortly before his standards trip, and it was very rapid indeed; I recall 2 turns per second vs 1 per 2 seconds (13 year memory though). Shortly afterwards we were both together and I managed to get into one by accident; I'd never seen him move so fast, and it took several turns to recover. Nothing should be taken for granted.

I also understand that the Bulldog has a flat mode as one went down on the beach near our field a few years previously. the crew got out but the QFI broke his nose as he landed flat on the wing and then had to crawl off the end, his late chute opening resulted in an injured back. To add to the fun, a nearby a/c trying to help, landed on the beach and ended up inverted, requiring the student from the first a/c to assist!

I would refute the comment that no Bulldog has inadvertently departed into a spin. My then best friend, and a keen rival on the sqn, managed to kill himself in one. He had a fit of pique and flew a very low level down the local high street (the reasons are not within the scope of pprune, thankyou) and during the subsequent wing over went into a spin and landed on the beach. He survived the impact but perished in the post crash fire. The BOI considered that he had not allowed for the strong wind and so tried to correct a perceived skid/slip during the turn (external references) and combined with some pre stall buffet the a/c departed. It landed flat and relatively intact, classic spin impact.

Anyway, enough of all that. the only advice i would offer to would be PPl spinnees is make sure you climb to a SENSIBLE height. We used transition level plus ground height as bale out height, plus 2000 ft plus 350 ft per turn anticipated= quite alot thankyou very much. Don't let some tosser spin you at 2000' 'cos he's done it loads of times and it's a C152. Make sure you have a good surface too, part of the hasell cx should be 'no homogenous surface' which just means not over water or cloud etc. the point being that if the sun is obscured you may find it very hard to judge the number of turns.

Finally, it's great to see such professional and esteemed debate, rather than the rantings and abuse so frquently present on these forums.

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Another day in paradise

Having spun 150's numerous times
over the years, I personally have never
had a problem provided the recommended
procedure was carried out. It is likely
that a misrigged aircraft may lead to
an abnormal recovery sequence.

I've never noticed a tendency to flatten in
a 150. I was a passenger when
a friend of mine spun a 150 from
12000',
We were exploring the absolute ceiling.
After a botched recovery we continued
inverted recovering at about 4000'.
Having learned nothing, (young and foolish)
we did it twice more, this time without
inverting. Recovering around 3000'
this time. The one thing I noticed was
that once stabilised there was little
change in the rate of rotation and
normal recovery actions brought
us out immediately. At no point did
it flatten in any way.
Eventually I got nervous and feigned
airsickness to convince my friend
to stop. Hardly to be recommended
but interesting for all that. It did,
however give me some confidence
in the relative docility of the 150 in a
spin. Perhaps misplaced.
As a suggestion prior to entering a spin,
perhaps a couple of stalls designed to provoke
a wing drop,should there be any
might convince you to do your
spins in another aircraft.

Having said all that I cannot recall
any incident where a Cessna 150
failed to recover from a deliberately
induced spin.

I've spun 172's too but always slightly
guilty at this abuse of a docile aircraft.
Some are very very reluctant to spin
and require firm handling.

The story of the Provost which
recovered after the departure of the
student was interesting. A very similar
thing happened to an Irish Air Corps
Vampire T55 (RAF T10). After failing
to recover from the spin. The QFI
ordered the student to eject, when he
did so the jerk of the seat caused the
Vampire to recover from the spin. The
QFI flew home with the wind in his
hair leaving the hapless student to
make his own way back.
In an odd follow up the student in his
helmet and flight gear walked to an
isolated farmhouse for help causing
the occupants to flee in terror fearing
they had been invaded by aliens!

Fifthcolumns

Interesting tale. IMHO the consistency that you (and others) have observed in your experiences may say more about the way the controls were handled during entry and recovery than that the type concerned will never bite.

In the RAF the two seat Vampire was the T11. I was trained on those and one of our instructors was up with one of my course doing spinning when they had a delayed recovery. The QFI took control and after several more turns said standby to eject. That was enough for the lad who went there and then. As in your case the T11 then recovered so the QFI flew it home. We watched it taxy in without a lid and no stude. In came the QFI “I’ve lost me lad” he exclaimed. Made quite an impression on us at the time.

We often wondered whether the change in airflow from jettisoning the large canopy (presumably a loss of some lift at the front) or the seat firing, or both, could have been what triggered the recovery. My mate landed in a farmers field, very ploughed, very muddy and in the pouring rain. He got up and as the farmer approached tried to speak. All that came out was a high pitched squeaky voice that said “Isn’t it a lovely day?”

JF

T11 I knew that, really I did.
That'll teach me to check my facts
before commiting pixels to CRT
In fact having done so it turns out
that the spin was inverted, the student
ejected at 10,000', the Instructor
rode it down to 5000' and was
about to eject when he regained
control. It was concluded that
the absence of the canopy was
the major factor in it's recovery.
It seems that the Vampire had
a tendency to go inverted from an
entry to a spin.
And the terrified inhabitant was
a farmer on a donkey cart!
Later,apparently, this piece of
accidental test flying was written
into the manuals by DH.

Maybe they should have modded
the pilots notes for the type.
'In the event of a failure to recover
from a spin - EJECT STUDENT'

That would have been sobering reading
for tyros.

This particular student holds the
distinction of being the only member
of the Irish Air Corps to eject from
an aircraft. The Vampire was replaced
by the Fouga Magister which didn't have
ejection seats. Not much progress there.

Similarly, during the war years the
pilot of a Miles Magister in a spin
stood up to bail out, only to
find the aeroplane recovered possibly
due to the disruption of the airflow.


I agree with your point about the
correct and positive recovery actions
for spins. My friend flew a lot
of aerobatics so he had plenty of
experience of inadvertant spins.

He drove like that too, he could spin
a car as easily as a aeroplane.

I wonder though. would the two
lucky individuals concerned, qualify
as members of the Caterpillar club.
Considering the aircraft were not lost?

[This message has been edited by fifthcolumns (edited 22 September 2000).]

As I say, the Bulldaog student qualified, so I don't see why not. They'd also qualify for the Martin baker club too I guess.

------------------
Another day in paradise

The bulldog flat mode is an interesting subject. I recall the reports on the beach incident to which 212Man refers, and several trials to try and find this alleged mode - but I don't think at BDN we ever did. It was also asserted to me over a beer recently by a well respected author of aviation textbooks that it has this mode.

But, can anybody genuinely report having seen it who can inform me further? I'm not personally convinved about this flat mode, and suspect that the high rotational mode is what caused these accidents (which is rather flatter than the normal erect spin in the Bulldog).

Re: the Vampire incident. I was told (whether this was genuine fact or local urban legend I'm not sure) of a Canberra spin trial, with a crash dummy as ballast in the nose couch. The aircraft was unrecoverable, until the pilot ejected after which it self-recovered. It then crashed near to another airfield and a couple of RAF fireman got medals for their heroic rescue of this crash dummy!

G

[This message has been edited by Genghis the Engineer (edited 24 September 2000).]

GTE,
I am intrigued by your suggestion that the 'high rot' mode is flat, I perceived it as steeper than the normal spin. I guess this only goes to show how disorientating a spin can be, even when anticipated. I distinctly remember on my demo, the nose tucking down and the rotation 'winding' up dramatically to give a real blurring of the ground.


------------------
Another day in paradise

With soem 400hrs on Bulldogs,and living under the Old Sarum circuit - in fact I am just penning off a fax to get them to do an intial trip for my daughter to include a spin (!)- on London UAS all those years ago - gawd nearly 25 - we found each aircraft was sensitive to fuel load, single crew of dual,and of course which way you span it - it was hard work to spin R but IIRC semed to posesses some very strange characteristics. We were on a summer camp IIRC when the Southport beach fiasco occurred. As a dumb stude,so long as you remained positive in entry and positive in exit, on the whole there was never a problem. The problems arose because the stude was afraid to make the aircraft work for him, and so it went off on an aerodynamic jaunt of its own!

The hairiest I ever had was doing the aero's competition (practice) at height (usual recovery by TA + height of ground). this involved a quarter rolling circle, which if you really wanted to cock up in the early days you could use as an inverted entry to a spin. Usually you were running out of energy as you went round anyway and if you kept the nose too high in the rolling entry, you could wash a load of kts off v quickly.

Ah, sunny days with oil under the aircraft.

Just a thought but in reading all of this really useful information I have come to the conclusion that if I am ever in a spin and cannot recover, as a last resort I will try opening the door/canopy and even standing up, putting out an arm, and if that fails, I will throw out my passenger.

Reheat,
your remark about oil under the a/c reminds me of an incident I had. the friend I mentioned above, and I were always trying to outdo each other, one day he came back and told me he had recovered from a stall turn inverted, rather than pulling through. So, off I went to try the same; discovered how slippery the 'dog is going down vertical and how inefective the elevator is when applying negative g. Also, we had a restriction of -2g i think it was. Eventually recovered inverted at some horrendous speed and slightly over the 8second -ve g limit, and RTBd a bit sheepish. Thought i'd got away with it until I saw the engineers mouths drop as they approched the a/c after shutdown. It's amazing how spectacular a pint of oil can look when spread over a fuselage!

Happy days, indeed.

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Another day in paradise

[This message has been edited by 212man (edited 27 September 2000).]

Interesting stuff! The guy who checked me on a low-level endorsement showed me what he termed as a `mustering stall` (Aust), where for example, you roll 30+ degrees to the left, boot in more left rudder than required, then simultaneously roll out, and apply more (max) left rudder, giving crossed controls. When it lets go, (at a speed markedly above stall speed) in this instance, it will flip you over in a nasty fashion, and if you leave the ailerons in the same position as at entry, it will enter a spin very rapidly as well. If the power was left on throughout, and assuming the engine hadn`t cut, the ensuing spin had the sweat from your forehead flying the cockpit pretty swiftly. The quickest recovery seemed to be cut the power, push foward, opposite direction rudder, and a modicum of aileron in the same sense as the rudder. The outcome of the initial exercise could never be predicted, but the recovery always worked. Can`t remember alt loss.