Display pilot Bill Ramsey reveals a few of the considerations facing airshow pilots the world over, and he wants us all to bear them in mind before we put the boot in!
Like many display pilots I occasionally venture onto enthusiasts’ forums to get some feedback as to how the public thought the airshow had gone and yes, it’s lovely when people have enjoyed your display. But it’s the criticism that can be most useful, together with the videos – for most of us would never get to see what our displays actually look like otherwise.
On the other hand, uninformed criticism is frustrating, especially when it is, well, just plain wrong. I thought therefore it might be of interest to this audience if I did a short article about some of the many and varied factors which can make a display appear less than brilliant to the casual observer, but which may actually have been technically outstanding.
Never forget that whilst we love to entertain, our primary responsibility is crowd safety.
Don’t get me wrong, anybody can have an off-day, so it might have been genuine, self-induced rubbish but, in my experience, the harshest critic of a display pilot is usually himself, or herself. As you’ve probably seen, the professional military teams always video their own displays and a full and, believe me, frank debrief is always carried out before the next display. A display pilot who isn’t both self-critical and open to reasoned criticism probably won’t last long.
I thought I’d start with the biggest and universal factor – the great British weather! Low cloud and rain are I suppose obvious, but what about visibility on a lovely summer’s day? On the ground it can appear wonderful but in the air it maybe a different story. The longer the weather is settled the more all the crud in the atmosphere descends towards the surface, so for our intrepid pilot, the airborne visibility may be much reduced. Looking into sun during the late afternoon can be almost like fog, known as ‘goldfish bowl’ conditions, removing many of the visual references and cues necessary for an uninhibited display. Now, imagine it’s also a seaside show over a calm sea – I promise you, this is now becoming hard work!
The less experienced the display pilot, the more this (and all other weather factors) are likely to affect the display. Don’t forget that for most RAF displays there is often a new pilot each year and therefore a new and steep learning curve each season. In my first year on the Tutor, I flew a flat display at Sanicole on what appeared to be a lovely autumn day for exactly this reason.
Whilst I’m on the subject of things you can’t see, air-turbulence deserves a mention – you know, the bumps you sometimes get whilst flying off on holiday. This can degrade the performance of light aircraft in particular, to the detriment of the display. For those who have been lucky enough to go there, Jersey can be a classic example of this with its beautiful bay, surrounded by high ground, over which a horridly bumpy wind sometimes blows. In bigger / faster aircraft which are normally flying turns close to the aircraft’s permitted G limit it can sometimes be necessary to fly turns with less G to avoid a bump taking you above the airframe limit.
Other things you can’t see but really mess up (in particular) light aircraft displays, are the height of the airfield above sea-level and temperature. So, for example, on a hot day at Biggin Hill (600 feet above sea level) I once had to stop my full, aerobatic display and revert to the flat one simply because the Tutor’s little engine couldn’t provide the power in the conditions. I doubt if it looked good to the crowd but there was nothing I could do about it.
Last, and absolutely the most important, of the invisible elephants in the room is the wind, and this affects every single display greatly! Perhaps oddly, it is not the size or weight of an aircraft which determines how much it is affected, but it is its speed which governs everything. The slower it goes the more the effect, so for example, an Extra as flown by The Blades reacts exactly the same in the wind as the Vulcan, as both are being flown at around the same speed. I don’t know about you, but I find that gob-smacking!
Another fact you may not be aware of is that the wind usually gets stronger as you go up. So on a windy day with say 35 knots of wind on the ground, this will probably be 45-50 knots at display heights. Oh, and the direction it blows from usually changes as well. Talk about 3D chess!
So, what do I mean by the wind effect varying with aircraft speed? Well, the maths are a bit complicated so don’t expect me to explain them! But let’s say there are two aircraft flying in the same direction with a wind of 40 knots blowing directly across them from the left. One is flying at 120 knots (like the Tutor) and one is flying at 420 knots (Typhoon for example, typical fast-jet speed). The slow one will have to point 20 degrees into the wind just to maintain its direction and track over the ground. The fast one will only need to point around six degrees into the wind to do the same thing. To put it another way, the consequence of getting this wrong is much bigger in a slow aircraft than it is in a fast one.
Now let’s put the same wind directly in front of, or behind, our aircraft. This wind changes the Tutor’s groundspeed (what the crowd sees) by a whopping 33% of the speed indicated in the cockpit, whereas for our Typhoon it’s a much less daunting 10% or so. This means that your Tutor, Lancaster or even Vulcan have to spend a lot of time fighting back into the wind to stay in front of you during a display in these conditions. This doesn’t make for the best display, but cannot be avoided…..
The worst wind of all is the one which blows directly at you, the crowd. For your safety, CAA regulations lay down very strict minimum distances in front of the crowd which display aircraft must keep outside of. For the reasons above it is necessary to display further away from the crowd in this strong “on crowd” wind to avoid infringing these safety distances. Each time our slow aircraft passes in front of the crowd, flying left-right or vice versa, if the pilot did not account for the drift from the wind, the aircraft would end up around 1000 yards behind you! So if you sometimes think a display looks a bit more distant than usual, maybe that’s the reason?
Of course, in the real world the wind is usually not in front, behind or across the display, but somewhere in between. It’s rarely the same twice so there’s a lot going on in the pilot’s mind during every display, on top of all the other variations I’ve mentioned, and actually flying the aircraft of course!
Well, that’s enough about things you can’t see, but I just want to mention briefly two other things I often read. First “such and such a type doesn’t display half as well now as it did many years ago”. Well, maybe people are just trying to preserve its flying life? More importantly however, the regulations covering what you can and can’t do in a display have changed almost beyond recognition – again, it’s all about public safety.
Lastly, I can’t go without mentioning the famous Vulcan howl and I’ve read more tosh about that than almost anything else! First, from my ringside seat, I promise you that none of the pilots handle the throttles in any way differently to each other to generate the howl. Whilst I’m not at all sure about all the magic that makes the noise, I am pretty sure the crowd hears it best when the wind is blowing it towards them. Simples!
I hope this has been of interest and maybe will help people to decide better if they are making a fair criticism when they get home from a show. If anyone – display pilot or otherwise – wants to disagree or ask a bit more, please get in touch by posting a comment.
Enjoy your display season.