Private Pilot Private Exam

You are calculating density altitude for a mountain pass at 11,500 feet MSL and find it to be 14,800 feet MSL. What should you do?

1. Continue as planned since density altitude is irrelevant

2. Re-plan your journey to avoid the mountain pass

3. Continue since mountain thermals will help

4. Fly at a lower altitude through the pass

The correct answer is: Re-plan your journey to avoid the mountain pass

When you calculate the density altitude and find it to be significantly higher than the actual elevation of the mountain pass, this indicates that the air is less dense than standard atmospheric conditions would predict at that altitude. In this case, flying at a density altitude of 14,800 feet MSL at a mountain pass that is only at 11,500 feet MSL suggests that the aircraft will perform poorly compared to its performance at sea level or in denser air. High density altitude negatively impacts aircraft performance in several ways: it reduces engine power, thrust, lift, and overall climb capability. This can make it particularly dangerous to navigate through mountain passes, where required performance (like climb rate in case of an obstacle) can be critical for safe passage. Re-planning your journey to avoid the mountain pass is the prudent course of action. By doing so, you ensure safety during your flight by avoiding challenging conditions that may lead to situations where the aircraft cannot maintain altitude or performance standards necessary to navigate through the pass safely. Choosing a different route or altitude can provide more favorable conditions and enhance safety during your flight.