Enjoy Your Stalls

My introduction to flying, and my most unforgettable year in aviation was 1944, when at the tender age of 19 I progressed through Tiger Moths – Harvards – Kittyhawks and Corsairs in the space of nine months, and finally operations – still a teenager – rather like throwing the baby into the deep end to teach it to swim! From ‘day one’ until discharge in 1947 I never flew an aircraft without wearing a parachute. Since that day, I flew mainly ‘light aircraft’ up till 29th December 1993 never with a parachute(except for some parachutist dropping) – indicating that they are quite a different ‘animal’ from our wartime aircraft – and much safer in every respect!

During my 62 hours training on DH82 Tiger Moths at Harewood my log book shows that I practised spin recoveries on 19 flights, but stall recoveries on only 4 flights, yet as late as May 1993 I was involved in teaching spin recovery to B Cat instructors at Ardmore, many of whom had never experienced a single spin! This was done as a new requirement by CAA after a number of spin related fatalities primarily in four-seat light aircraft, possibly due to inadequate tuition!

As an instructor in later years I always felt sympathetic towards students who exhibited a fear of stalling, due to my own frightening experience whilst on an Air Training Corps course at Ohakea in 1942 when I was subjected to a rather frightening stalling demonstration in a twin-engined Airspeed Oxford trainer, flown by a Squadron Leader Breckon DFC who had returned from flying bombers in Europe. As I walked out to the Oxford, the previous cadet said to me “Ask him to do a stall” – which I did, although I really didn’t know what a stall was!  When S/L Breckon eventually demonstrated one, I was completely caught ‘off guard’ and the Oxford felt to be dropping forever – and the terrible sensation caused me to almost choke, and couldn’t get a word out when I attempted to ask him to stop it! That terrifying ‘dropping’ sensation remained with me for the rest of my Service days, but although I never experienced the same frightening sensation flying Tigers and Harvards – I never straight-stalled either a P-40 or a Corsair during the three years I flew them – apart from every landing which were three-pointers!! Another reason for that being that neither aircraft had a very good history of spin recoveries, which in fact were not permitted in the Corsairs. My good friend Keith Wakeman of Christchurch proved that, when in a mock dogfight with another Corsair over Bougainville at 11,000 feet, he struck the slipstream of the other Corsair throwing his into a violent spin from which he couldn’t recover, baling out  at approximately 1,000 feet with his parachute just opening in time. Although not far from base, it took him three days to penetrate the thick jungle to reach the coast, and eventual rescue. Another similar situation caused the sad death of New Zealander AVM Sir Kenneth Hayr at Biggin Hill on 2nd June 2001 when his DH Vampire aircraft struck the slipstream of a heavier DH Sea Vixen causing the Vampire to enter an unrecoverable spin.

On arriving at No 4 OTU at Ohakea on 1st August 1944 and never having previously sat in a P-40, there was a fair amount of apprehension knowing that within two days we would be flying one, and that most previous OTU courses had suffered at least one fatality, usually from ‘spinning in’ as the P-40 wasn’t very forgiving in that respect. Statistics show that within New Zealand nine P-40’s were lost due to spins, and another eight from diving into the ground, which were probably also associated with attempted spin recoveries. Within New Zealand and the Pacific, statistics show that 29 P-40’s were lost from mid-air collisions, which was another cause for concern! Consequently, with only 113 hours P-in-C time logged, at Ohakea I never intentionally stalled a P-40, except on landing. Notwithstanding that we spent many hours of virtually continuous aerobatics, singly and in line-astern fours formation behind combat experienced instructors. Our low experience is probably why our recommended aerobatic speeds in P-40’s were at least 50 mph, and in the Corsairs 50 knots, above what the more highly-skilled demonstration pilots use today. Spins being prohibited in Corsairs was a good reason for my reluctance to ever conduct any stalling practice in them, but later during flying practice sessions I enjoyed many hours of virtually continuous aerobatic manoeuvres. During continuous loops one had to closely monitor the cylinder-head temperature reading, closing the cowl flaps as speed increased in the dives, and opening them again as speed decreased in the zooms in order to keep the CHT as constant as possible. Using 300 kts for loops and 330 for Immelmans they covered several thousands of feet of airspace, and over Cambridge I occasionally performed a dozen or so without a break, just making out a good friend below frantically waving her tea-towel!

On my very first flight in P-40 NZ3082, on our second day at Ohakea 3/8/44, after two area familiarisation flights in Harvard NZ1061, I enjoyed the thrill of hearing and feeling the beautiful V-12 Allison up front, and when airborne was rather mesmerised by the long nose which appeared to be pitching gently up and down, after the much shorter nose on the Harvard. I apparently didn’t monitor the climbing speed, so when I began to turn right towards Palmerston North at about 2,000 feet, the horizon suddenly began to rotate quite fast in the opposite direction, which didn’t take me long to realise that I was experiencing my first unintentional stall, and spin commencement. What saved my life were the almost daily ‘snap rolls’ we had practiced in Harvards at Woodbourne, even during instrument flying training with other students! – so I instinctively applied “stick forward and opposite rudder”, which stopped the rotation instantly after about a third of one turn, and NZ3082 stopped rolling – completely inverted. My brain immediately said one word “AIRSPEED” so I allowed the nose to drop a little to gain more airspeed before attempting to roll level again. A memory I will never forget whilst flying inverted was the tall white building of the T & G Insurance Co building in Palmerston North appearing inverted in my windscreen!

Although I never snap-rolled either a P-40 or a Corsair – during local flying practice at Guadalcanal one day in December 1944 I did see another Corsair pilot snap-rolling a Corsair at quite low altitude – probably an ex instructor with over 1,000 hours flying experience, but it did prove that by reacting quickly enough, one could probably prevent a spin from developing, even in a Corsair, as a snap roll is basically the first turn of a spin, normally entered in the horizontal. In No 14 Occupational Squadron in Japan in 1946, one day whilst having a friendly dogfight with an RAAF P-51D Mustang, I had no problem in sitting behind him in a turning duel – amused by watching his Mustang flicking right and left due to the airflow breaking away from his thinner laminar flow wing. I could just picture the pilot quickly hitting “stick forward and opposite rudder” each time it flicked – just I had done in the P-40 at Ohakea. With its thicker-section, hi-lift aerofoil the Corsair would merely buffet when pulled in to the tightest of turns, when we were taught to lean hard forward with our head bent right down level with our heart to avoid blacking out – and it worked – even though one lost forward vision temporarily!

Whilst flying Corsairs we occasionally did Instrument Continuation training in Harvards, with another pilot as safety-pilot – during which the Harvard felt like a real toy!

Similarly, modern light aircraft also initially felt like toys compared with a Harvard! I once hired a small Grumman trainer from Auckland Aero Club – curious to investigate its stalling characteristics – only to find that it virtually had none – which isn’t very desirable for a trainer! A similar situation existed with our high-winged Piper Tri-Pacer, which just refused to stall with the wheel held right back against the stops – which I assumed to be the result of limited elevator movement.

Regardless of piloting technique, any aircraft badly loaded in respect of ‘weight and balance’ with the C of G behind the rearward limits can, if stalled, readily spin with recovery either difficult or impossible – with fatal results.

Although I could quote a number of fatal accidents probably resulting from poor weight and balance loading, space only permits one example involving the “Rallye” aircraft described below, killing the pilot Lloyd Seabrook and three passengers in a spin at Matamata airfield 7th March 1965. As Seabrook Fowlds were agents for the French built  Rallye aircraft, Lloyd wrote the following in the aircraft handling notes.

It made me wonder when teaching on Cherokee 140 and Cessna 150/152 trainers, why a simple stall, with or without a mild wing-drop, was considered such a big deal!    It also often made me wonder at the CAA insistence that all stall training had to be conducted above 2,500 feet AGL – when we were unrealistically teaching pilots how to deal with an unintentional stall very close to the ground – in aircraft which are generally loath to stall at all!

I am not aware of the current practice today, but an adverse effect of only conducting stall training and flight testing above 2,500 ft AGL is to imprint in trainees minds that any stall below that height is potentially dangerous, whereas in all the modern factory-built types such as Cessnas, Pipers, Beechcraft, and Grummans etc this is not the case. In fact it tends to create fear and not confidence in ones ability to deal with the situation. During the latter 20 years of my 30 years of instructing I would have conducted thousands of stall recoveries in the Ardmore low flying area, and taught all CPL and Instructor trainees how to conduct all types of stalls, including fully-developed, even up to the first turn of a spin, at 600 feet AGL – with recoveries always safely completed by or above 400 ft AGL or water – giving all candidates much more confidence in the knowledge that subject to using the correct recovery techniques, virtually all stall situations are safely recoverable or preventable. I consider a scared pilot a dangerous pilot, and in my opinion if they cannot demonstrate a simple wing-drop stall and recovery at 600 feet AGL they shouldn’t be allowed to carry passengers – or even fly an aircraft!  I occasionally remedied the fear of a number of my 596 PPL Issue candidates who displayed obvious fear when asked to conduct a wing-drop stall recovery – by later taking them to the low-flying area, and after about half an hour or more of many safe recoveries they usually didn’t want to terminate the exercise – gaining confidence which in my opinion made them much safer pilots to be carrying passengers!

Since writing the above I have come across a relevant observation by Air Commodore C. P. Symonds RAF writing in 1944; “Lack of confidence is a major cause of flying accidents, operational failures, and psychological breakdown in aircrews”.

It is my belief and opinion that by conducting stall recovery, and spin prevention training at much lower altitudes than 2500 feet, pilots gain far more personal confidence in their own ability regarding possible stalls occurring at low levels, say on an approach. The secret is instantaneous correction at any stall onset, which should become second nature, preventing any need for spin recovery – and should be mandatory for all instructors, Commercial Pilots, and Private Pilots with more than 200 hours P in C time logged.

However, I would not advocate students and low-hour PPL’s being cleared to conducting solo stalling practice at such low levels, nor the practice to be adopted for homebuilts, unless that organisation has official clearance for particular aircraft types.

My opinion is that during my years of flight instructing – 1964 to 1993 – the major emphasis by FTO’s on minimum height loss recoveries, was at the expense of the far more important “spin prevention” tuition, in the form of wing-drop stalls. Too much emphasis on minimum height loss during either a basic or a wing-drop stall recovery, can in fact result in pilots tending to begin to raise the nose to prevent height loss, before the wing is fully unstalled – which if slightly out of balance can easily create a spin situation.  There are at least two well known examples of commercial airliners (both Airbus models) crashing due to crews continuing to hold their aircraft in a climb attitude whilst descending rapidly, unaware that they were in a stalled situation, until fatally crashing. In both cases, improved pilot training was advocated.

The following is a spin prevention exercise, not a spin recovery exercise – which should not be necessary if a pilot is proficient with the former!  The essence is to immediately check forward the instant a stall is detected, and if necessary apply sufficient opposite rudder to prevent yaw towards the lower wing.  Unless one is extremely close to the ground or water, there is really no urgency in attempting to raise the nose, which as I have mentioned can in fact precipitate a further stall – and if unbalanced – a spin.

I would mention that I have frequently flown most models of Cessnas and Pipers, testing their stalling characteristics, proving that they can in fact be flown in virtually a continually stalled state, with no risk of spins developing, using basically the techniques described below. All it involved was, using a low power setting of 1800-2000 rpm to maintain height, and each time the nose pitched, checking gently forward on the wheel which immediately unstalled the wing, and using sufficient top rudder to prevent yaw if a wing-drop commenced – then with wings level again, immediately gently easing back on the wheel to re-stall again. By using the above technique and power settings, one can virtually maintain constant height during continual stalls – as I have used in “incorrect flying” displays at low levels in both Cessna 152’s and Piper Cherokees!  Even a Cessna 402 twin merely commences a gentle oscillating pitching motion on entering a stall situation.

ADVANCED STALLING  (abbreviated)

AIM  To recover safely from a fully developed stall with wingdrop – to prevent spins from ever developing!

PRINCIPLES AND CONSIDERATIONS

Causes of wingdrop (a) Damage or Ice, (b) Propeller effects of Slipstream rotation, and to a slight degree torque. Asymmetric Blade Effect off-setting thrust.  (c) Weight imbalance. (d) Severe turbulence. (e) Pilot Induced – imbalance near the stall, and incorrect use of aileron to pick up the dropped wing.

ENGINE HANDLING  “power on” entry induces wingdrop, normally to the left as clockwise rotation of slipstream tends to increase angle of attack on left wing, thus stalling it earlier than the right wing. Engine torque may also cause some tendency to roll to the left, if full throttle is applied quickly at slow airspeed.

AIRMANSHIP  HASELL CHECK  Height – Airframe – Security – Engine – Location not over built-up areas etc, and Lookout  – making at least two 90° turns in opposite directions.

AIR EXERCISE

ENTRY  1800 rpm and Full Flap  (30° Cessna 152)

SYMPTOMS  Rapid roll at Stall

RECOVERY  (When wing has dropped approx 30° in a stalling exercise)

  1. FULL POWER–WHEEL FORWARD–TOP RUDDER (All together)
    PAUSE
  2. ROLL LEVEL centralising RUDDER
    PAUSE
  3. RAISE NOSE SLIGHTLY ABOVE HORIZON – REMOVING FLAPS
    PROGRESSIVELY

The reason for the PAUSE between 1 and 2 is to give the wing a few seconds to unstall prior to rolling level.

The reason for the PAUSE between 2 and 3 is to avoid creating a secondary stall with rudder still applied – which could result in a spin in the opposite direction! – so level the wings and centralise the rudder before attempting to commence a climb.

In 1979 I flew a 130 hp French-built Cessna 152 demonstrating it to Indonesian Air Force top brass at the International Airport at Jakarta, and the following day at the military airfield at Yogyakarta on the south coast of Java. In the two days I made approximately 20 flights, each including aerobatic and spinning demonstrations, and after landing, one of their young instructors said to me “If I fly with you I live long time!”       He had previously been flying MIG’s and they had one sitting on a plinth outside their training establishment.

My advice to all is to try out your wingdrop stall recoveries exactly as detailed above, initially at altitude, and I guarantee that in future you will enjoy your stalls!  – and live long time!

An interesting observation and conclusion which I have always applied, including to myself, is that an aircraft will only do what you let it do – or make it do – so it’s up to you!!

My final opinion is that pilots who don’t enjoy flying, shouldn’t be flying!

Bryan Cox
Tauranga