WOW...!
....just completed a test run from KLXV at 10,000 Feet ASL, over the Mountains at 12,500/15,000 Feet ASL, and a steep dive down to KASE at 8,000 Feet ASL.
A scary trip!
At those altitudes it was impossible to get my Cessna 150 to accelerate steeply over the Mountain, and I only just managed it in my Cessna 182 RG with its 235 HP engine*!
Little normally aspirated Piston props are not very happy at Arizona's hot, high altitudes, even with juggling with the Mixture Control!
Paul...G-BPLF...FS 2004...FS Nav... 8-)...!
* ....time to fit it with a Turbocharger...

....(TR182 Turbo Skylane RG)
Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.