I tried the same maneuvers as Paul describes below in my Cardinal RG with the same results. The altitude loss was reduced by increasing the bank angle, but the "degree of difficulty" also increased. The best technique was to use a fairly steep bank angle - at least 45 - and use the back pressure appropriate for the airspeed (you would wish for AOA information about this time!), starting with essentially no back pressure and increasing the G loading as the airspeed increases. The turn ends with a fairly high airspeed and significant G loading. I found that it took about 700 ft to make the turn, and I simulated getting to the runway by turning 225 degrees one way and 45 the other. As the bank angle increases, however, it gets to the point that I can't imagine doing the maneuver close to the ground - no horizon, ground rapidly turning, bank angle changing, airspeed changing, G load changing, all at the same time and all with no room to spare. Sounds like what a profession aerobatic pilot would experience every day. My conclusion is that 1,000 feet would be the logical decision point and the bank angle I would use is between 30 and 45. Problem is, as I'm sure some have found the hard way, that back pressure control is critical. Without an AOA I don't see how it could be done with any precision - at least by someone of my experience and skill.
The best method is undoubtedly to make sure ahead of time that the engine will run for at least a minute at full power - but how do you do that? That also has some uncertainty.
Gary Casey On May 14, 2006, at 3:00 AM, Lancair Mailing List wrote: A friend of mine just investigated this in a Cherokee 180 with the following results: First, of course, I tried what I was taught: power to idle, 70 knots, standard rate turn (3° per second). I didn’t pay any attention to the bank angle but suffice it to say, it was rather shallow. The VSI was reading 800 FPM, and of course, after turning 180°, I lost 800 feet. Next I tried 45°, using the attitude indicator and ignoring the rate of turn. Holding back-pressure to maintain 70 KTS, the VSI was indicating 1,000’ FPM, but as expected, the stall warning horn came alive with its burbling, not a full horn. I got around the turn in well under 60 seconds, netting an altitude loss of only 600’. Then I tried the same as above, but I didn’t hold any back-pressure. The nose dropped to 95 kts which is a fairly steep nose-down attitude, one which would alarm anyone who is close to the ground. VSI jumped to 1,500 FPM, again, something that would freak-out anyone trying this close to the ground who has never tried it before. Getting around the turn took very little time, netting only a 300’ loss in altitude. I was impressed. At a 60° bank with no back-pressure, the ASI jumped to just over 100 kts (nearing the yellow arc). The nose-down attitude was uncomfortably steep as I saw through the eyes of someone 700’ from the ground trying this maneuver for the first time. My windscreen was filled with farms, roads and buildings and not much in the way of a horizon. The 180° turn was accomplished very fast, so fast that the VSI never stopped moving. It peaked at well over 1,500 fpm, close to 2,000. As I pulled out of the dive/turn, I picked up 100’-150’ while converting the excess airspeed to altitude, netting a total loss of 500’. Although a 500’ loss seems ok, I had to lose close to 700’ to get it. If the ground was 600’ below me when I started the turn, I would have been a smoking hole in the ground.
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