Two thoughts:
1. re: Density altitude, all the usual caveats apply, but I'd add be careful in gusty conditions and with mountainous terrain around the airfield or else trees etc which can affect the microclimate. One thing in particular to watch out for is rivers on the take-off / approach which can be quite cold and cause turbulence or downdrafts just when you don't want them.
2. For most purposes, rough field technique in a nose wheel can be confined to keeping the weight off the nosewheel as much as poss with up elevator. On occasions where it's really rough and you want to get off really quick, you can use full flap. The technique I was taught in Idaho in a 172 is start with one notch and as the speed climbs drop full flap and count to three to allow for the slow electric descent of the flaps, then pop the column back slightly to get off the ground in ground effect and then keep the nose down, bleeding off flap to one stage while in ground effect and then accelerating and climbing away.
This works a treat in the Super Cub where you can just pull full flap in an instant, then bleed it off more slowly in ground effect, trading lift for speed, like a cyclic control or collective or whatever it is they have in helicopters. It does work too in an aircraft with electric flaps, like the C172, but it's not quite so intuitive.
QDM
Last edited by QDMQDMQDM; 9th October 2002 at 11:01.