Bonanza Man wrote:This one had nothing to do with DA but rather a very poorly flown departure. He left his gear down and then went too fast, the faster you go in a Bonanza with the gear down the worse the climb rate. All he had to do was pull back on the yoke but he never did.
Another case of not really knowing your airplane's capabilities in different scenarios.
Soy followed up:
"Good point. There are no universal rules. Everything has exceptions. Of course if you are taking off into descending terrain, you can be just a little less cautious - but as Cary points out - you gotta out climb the terrain. The 70% rule will get you 50 feet off the airport - after that you need to use your noodle - and you better have thought about that before you start your takeoff roll."
When I left La Garita, I had exactly these issues to consider. I do know my airplane pretty well, after 11 years and 600 hours of flying her. As anyone who has camped near me, at Marble, La Garita, Oshkosh, etc., knows, I tend to "glamp" (pic from La Garita below) which means that although I may not be at gross, I'm running heavy. La Garita is roughly 3600' long, but 2800' for us small tire folks. Density altitude was about 10,000'. So I walked the runway and determined where halfway on the 2800' part was. Downhill, the terrain opens into the San Luis Valley; uphill, the terrain rises, and my airplane will climb, but not well and not at a rate that I really wanted to take off uphill. So although the wind was blowing pretty hard (windsock straight out), quartering from the southwest, I elected to take off downwind and downhill. I was airborne by the halfway mark, but I stayed within maybe 5' of the terrain until I had 90 mph on the ASI, which was just about at the end of the runway, then climbed out at about 200-250 fpm.

So knowing the airplane, keeping weight reasonable, "using your noodle", all play a part in a safe departure from a high density altitude airstrip.
Cary