HI Joseph,
Here’s a answer from Steve Ells:
Hi;
I recommend that you contact the mountain flying school you’ll be flying with and ask them. Another source is http://www.mountainflying.com, and the “Mountain Flying Bible” by Sparky Imeson.
Here’s one of Sparky’s Rules of Thumb for calculating TO distance when flying an airplane with a constant speed prop.
“To the standard, sea level takeoff distance, add 10 percent for each 1,000 feet density altitude up to 8,000 feet. Add 15 percent for each additional 1,000 feet above 8,000 feet”
He give the example of a Cessna 180 at MTOW under standard atmospheric conditions at sea level requires 625 feet of ground roll for takeoff.
At 7,500 feet it requires 1,100 feet for takeoff
7,500 = 7.5 times 10 or 75 percent (0.75)
625 + (625 x .75) = 1093.75.
Here’s a rule of thumb for density altitude effect on rate of climb for a constant speed prop airplane:
“Reduce sea level rate of climb by 6 percent for each 1,000 feet density altitude up to 8,500 feet and 8 percent for each thousand feet above 8,500 feet.
These rules should help you create the performance numbers for your airplane.
The Mountain Flying Bible is a must have for all pilots.
Best,
Steve
