100 box canyon exits in 2017 YTD

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CharlieTango
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Joined: Sat Jun 10, 2006 10:04 am
Location: Mammoth Lakes, California

100 box canyon exits in 2017 YTD

Post by CharlieTango »

Box Canyon Exits are required after 1 of 2 things occur when flying in a mountain canyon.

1) The terrain ahead rising faster than your CT is capable of climbing.
2)The Canyon narrows to where turning around becomes impossible.

Above are your 2 points of no return.

Your shrinking left arm is perfectly natural as the terrain rises, it is your enemy as it robs you of your energy stored as air speed and reduces your exit maneuver options to the ones that are the least fun and most dangerous. If your speed degrades below 80kts IAS then lower your nose or turn around.

Safe zones

* Cruise on the downwind side of a canyon with a crosswind so that your exit turn is into the wind. Do this to avoid drifting into the canyon wall when making an exit turn.
* Maintain 500 AGL or above the canyon floor. You need energy to exit and this 500' can be your trump card if all else fails.
* Safe speed zone is above 85kts IAS.


Use the vertical escape route first. Aerobatic maneuvers that exit on a reciprocal heading use a vertical path to change headings and work well for canyon exits but CT pilots can't practice these. We can do steep climbing or descending turns that in a CT can have extremely small radius and permit reversing your heading in a tight canyon.

With 500' or more to the canyon floor a descending steep turn is the essayist option. Lower your nose, retard your throttle and bank steeply with zero back pressure.
With 85kts IAS you can climb steeply and bank steeply.
In both cases above I bank steep without much wingloading. I trade the vertical for radius and the exit becomes effortless.

Worst case - low speed exit. If you get slow and low your easy options disappear and you are now looking at a steep level turn at minimum speed.

I have done over 100 canyon exits in 2017 and none of them were worst case, all of them were fun.



PS: Teardrops often work, it may not be intuitive to begin by turning the wrong way but often this provides extra room.
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