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Old 10th Aug 2010, 02:35
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Brian Abraham
 
Join Date: Aug 2003
Location: Sale, Australia
Age: 80
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A repost from http://www.pprune.org/military-aircr...alberta-2.html

Originally posted by WeeWinkyWilly
The Low-down on Low and Slow
What is the most common cause of airshow type mishaps, from historical safety investigation data?
I'm still haunted by some of the mistakes that I made over many low-level displays (jets/big radials/ 4 engined/glider/helo). I guess it's just a stage that you can go through in a military career. The motivation was never to stun the crowd, it was always that you had to/needed to show your peers that you could "cut the mustard".....mixed in with an element of immortality and "it won't ever happen to me". The mistakes were many and varied. On one (grad parade), due to comms difficulties with the Master of Ceremonies, I'd forgotten to arm the smoke before rolling inverted at 300ft overhead and pushing during the high-speed advent pass from behind the crowd. I then fumbled the initial lunge for the side-panel switch, and due to inattention/lack of "push", never quite getting the post-overflight inverted zoom height for the pull-through back over the parade ground. That ensuing pull-through was on the buzz/buffet/judder and I had absolutely nothing left to play with (but they told me later that it had sounded "awesome" all the way round the bottom) - and yes, with that all important visual aid of "smoke".

On an earlier display, after the work-up practice sessions at the satellite, I inadvertently left the ventral speedbrake out for the hammerhead tail-slide over the parade ground.....as well as over-pitching and not nailing it in the true vertical. To complicate matters I had a "licenced to interfere" rear-seater. Because of the extended board and due to the fully forward correcting stick input, it fell on its back and we did a turn of an inverted spin before the couples sorted themselves out and we found the nose-down vertical for the half-roll to line and pullout. My vivid memory is of the crowd below splitting to the four points of the compass - toute suite. The RH gear went unsafe (M.I. barber-pole) during the pull-out but I pressed on with the display. Why? The show must go on. I excused myself for that verticality cock-up on the grounds that the check-pilot in the rear had tried to show me his version of my display over the satellite airfield ten minutes earlier - and very nearly cancelled our tickets. I was not hyperventilating, but I was distracted. Anybody would be.
I resolved to get it right for the next grad, but for that, I managed a wholly different can of jackanapes. The final flypast to conclude the display involved approaching the dais at 300ft agl from crowd-front, erect, configured, whilst extreme-yawing L&R, wings-level, in orchestral metronomic syncopation with the band music. The final application of left-ruddered yaw was rushed due to a tailwind, the urgency being to peel off to the right in an accelerating steep turn whilst still short of the dais and while cleaning up. Unfortunately, running out of room, I broke the natural yawing cadence and overcooked it. Due to surprise (and bum reflexes), I only realised it as I was flicking past 90 degrees of left bank. I had little choice but to continue the rapid LH roll through the inverted and pull hard, converting to a dishing steep-turn right (and overspeeding the gear retraction). Friends on the ground, and familiar with the standard display, thought I was just cockily extemporising. I wasn't.

On another type (4 eng), due to a late night I screwed up the time hack at the briefing and ended up mixing it up with a formation of 4 Canberras- through departing the IP a minute early. I still have visions of aircraft flashing by left and right as they broke. Friends in the crowd told me that it looked for all the world like a coordinated cross-over and nobody criticised the inept stunt. Lead Nav told me later that he'd suspected that I'd got the on-stage time wrong, but said nothing.

In yet another fiasco, during a practice over the base I let the jet's nose drop badly during a garbage roll at 300 ft AGL. I'd always had limited success with that maneuver up to that point, yet I was loathe to drop it from my display..... as it was traditional. A visiting two-star brass-hat saw it and I got carpeted - but they never did any more than question my judgment.... not my competence, nor technique. I'd actually thought I was dead (face full of ground only) - and don't know to this day how I extricated myself. I eventually nailed that maneuver, as I had to. Why? Because it was always included in that display - no matter who flew it. The trick was to enter the roll nose-low and pitching up whilst adding power. Nobody ever told me, I worked it out for myself. In those years, one's training for displays was limited to getting nominated and sitting rear-seat with the incumbent for a run-through (two if you were lucky).

For the jet trainer display I developed a phobia about doing the stall turn at low-level and always did a very unobvious slow and ballistic wing-over in lieu. Whilst it was a solution for the phobia, it was probably more hazardous than a properly executed stall turn. But the phobia stemmed from a hung-up, over-ruddered stall turn over a satellite airfield. Nobody at home there. It would have been a very lonely unobserved death, a tell-tale pall of smoke in the far distance and no "ops normal" call. Later, in the big radial, I developed a phobia about doing anything but a stall turn to the right at low-level. That meant that, to be true to my tight sequence, I always had to enter the arena from stage right. I had many animated discussions with leader people at air-show briefs who just wouldn't accept that quirky foible. The rotten machine just didn't want to go round to the left - against engine/prop torque - so it was quintessentially a matter of survival to hold sway in any such argument. I flew that display so many times, mainly because of initial under-confidence, that I eventually became complacent. Two events nearly brought me back to earth. The first was a radio dropping out of its rack-mount during an inverted loop and the second was due to that uncontrollable variable of undetected wind-drift. The XO had already warned me about my Derry reversing too close to the display line and here I was, about to overfly the crowd-line. Halfway through the Derry I converted into an inverted turn away and became totally disoriented. I watched video of it later and it almost looked intentional, but it was merely a panic-stricken last-ditch attempt to avert further verbal laceration from the XO. So maybe you don't want to hear it, but more often than anybody would ever realise, display pilots are often reacting like a trapped mongoose. Whether victims of circumstance, nonchalance, overconfidence or just poor judgment, you will often be watching a man in impure survival mode - but never realising it unless a tragedy happens.

I normally felt at home in close formation at low-level but whilst playing "follow the leader/catch me if you can" at 300ft over my leader's AirForce alma mater one Sunday, returning from an air display, I instantly learnt the value of never underexpecting the unexpected. Without telling me, he'd let his buddies know that we'd be over at a particular time. I was slowly realising something was afoot because Lead had entered a quick orbit then set heading, leaving me on his wing on listening watch on the enroute VHF whilst himself slipping over to a secret UHF freq for a private chat with his mates. I wasn't privy and just staying riveted in echelon right when I suddenly saw lead enter what I initially discerned as a roll into a RH turn at 300ft. He may have called it - but on his "silent" freq. Almost too late, I realised that he'd apparently forgotten I was there and was slow-rolling right (i.e. into me) in the ontop. I popped up and slow-rolled to the left (over him) into echelon left. He never mentioned it later and obviously just assumed that I'd copied his R/T advisory and coped well with his oblivious pecadillo roll. In the interest of a quiet life and continued friendship, I never took him to task. Error leads to later terror.
On yet another 4Eng type an older, more mature WeeWinky developed an impressive end of display exit stage right that involved a lightweight, well below VMCA maximap flapped climb from 100ft to 3500ft at a body angle of around 45 degrees nose-up. Copilot was quite junior and trusting, but FE's were old salts and unhappy about it. I rationalised that even if we lost an outboard we were so light-weight that I could simply bring the symmetrical engine's P/L back quickly and stuff the nose down. Nobody in authority ever questioned the questionable practice and it became a standard. So much for authorisation and supervision in the days of yore. The impressive display sequence was the driver. Safety was all about not getting it wrong, never about safety buffers for malfunctions and misjudgment.... but I had that selectively covered too. CO had been hammering the more junior non-QFI display pilot for a series of overstresses. His excuse was that the g meter was well outa sight. I didn't have that problem. The g meter from my sailplane was always masking-taped to the AoA chevrons on the coaming in front of me - for my tight shenanigans.

But the closest I ever came to oblivion was in accepting a last minute invite to display a Blanik at a glider meet. As a grand finale to an impromptu thrown together sequence of barrells, slow-rolls, stall turns and loops, I dove short of the threshold, pulling up at 10feet/95knots for what was supposed to look like a loop but culminating in a severe nose down bunt with a simultaneous gear down and flap and flare. I'd done it previously with great flare in a plastic sailplane but the Blanik had quite different aerodynamics. The bunting transition to nose down was commenced far too slow and way too nose-high and that nose was very slow coming down to gain anything like flare-speed. The transition to flare was almost 20 knots slow but with max flap and the gear went down at touchdown - and the oleo bottomed out. The video looked good later and the clapping was genuinely enthusiastic as I raised the canopy. However a closer examination of the video disclosed a dark green stain down the lower front of the khaki-green flight suit. I've never come closer to screwing the pooch. It was my last ever flying "display". I never go to airshows nowadays as it would be too traumatic for both me and my family to see someone buy the farm. Those who've never done "display" should always consider their motivation for doing it and the high probability of becoming a statistic... or worse, doing a Ramstein rehash. There were many more incidents than those cited above but I became expert at rationalising my short-comings and congratulating myself for adapting to the situation (i.e. getting away with it yet again). It was only with elderly hindsight that I ultimately realised that I was surviving not by skill or cunning - but only by the Grace of God.
Perhaps the last sentence sums up show flying well. Far too many have bitten the dust.
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