oscardeuce wrote:
OK, without trying to open a can of worms, or place blame etc, at what point do we go from "aggressive flying" to out of control flying?
Many of us fly airshows under similar circumstances, and need to be vigilant we do not let the adrenaline get away from us. It sounds like he was near the edge of the envelope, and an engine coughed. If he had not been so close to the edge he may have been able to recover.
Again, not blaming the pilot, just trying to discuss how we can safely display these old aircraft.
Oscar,
I think you make a good point, as the safe operation of historic aircraft is important, but I think the term 'aggressively flown', like the term ‘flown in a spirited manner’ (which is often used to describe a display), is rather ambiguous, and might be interpreted by some that an aircraft was being flown dangerously, or as you say, close to the limits, when it couldn't be further from the truth.
Having read several articles by pilots who flew RR299, it was clear that it was flown to strict limits - that is to say the power settings were kept sensible to conserve engine life, (and also due to the fact that the Mosquito was operating at lighter weights than when in RAF service), speed was limited to around 260kts, and from what I remember, the g was limited to +3 and no intentional negative.
Therefore, the display was kept simple to stay within these limits, with no aerobatic manoeuvres being flown. As can be seen from the videos, these consisted of a series of climbs, descents & wingovers, and a like any safe display, one where speed is traded for height & height traded for speed.
According to an article on flying the Mosquito by Peter Henley, who flew RR299 for a number of years, this type of display worked well, giving almost 250kts on level passes, with the speed bleeding off to about 160kts at the top of a wingover, and recovering to just under 250kts again on the next level pass.
This matches up pretty well with what the speed estimates in the AAIB report where, and the routine being flown on the day of the accident would have been similar to the sequence in the videos, although Barton was a smaller airfield than North Weald, which was where the display was in the two videos above.
Now, one factor I haven't mentioned yet is the single engine safety speed of the Mosquito, because with any twin engined aircraft, this critical in the display environment as the airspeed could fall below it, during the apex of wingover for example.
The Pilots Notes for the FB.VI aren't very clear or precise about it (and Peter Henley mentions this in his article), but state that "Although safety speed may be a little less in some cases, particularly at light load and with narrow-blade propellers, it is recommended that 175kts be attained before starting to climb, especially if paddle blades are fitted" (which, as he mentions, RR299 did).
My personal belief is that RR299 was not being flown in a ‘dangerous’ or 'close to the limits' manner during the above videos, or during
the fatal Barton display. The AAIB report supports this, as it does not conclude that the crash was caused by the manner in which the aircraft was being flown.
Cheers
Paul
P.S. Here’s another video of RR299 taken 12 years earlier:
http://www.youtube.com/watch?v=OgijBdX-yPk