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Buckaroo

Box canyon CT flight procedure question.

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Buckaroo   

Remember awhile back when the Icon engineer and his passenger entered a box Canyon and stall spun and were killed trying to exit? 

If you entered a canyon that turned out to be a trap how would you handle the 180 in your CT? In Montana we have thousands of these potential traps that sneak up on any mountain flying pilot. 

So how would you handle a safe exit? Lets say you enter at cruise with -6 flaps. A Chandelle? A hard g 180? Slow down and apply 15 of flaps followed by a as needed turn? Ideas??

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I went to a mountain flyin seminar at Oshkosh a couple of years ago.  One thing I remember is that in any canyon or situation with sharply rising terrain on both sides, its much better to hug one side so that you have more room to try a 180 if you get boxed in.  Also, the instructor said to fly at reduced speed, to minimize turn radius if you really need to make that turn and GTFO.

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42 minutes ago, FlyingMonkey said:

I went to a mountain flyin seminar at Oshkosh a couple of years ago.  One thing I remember is that in any canyon or situation with sharply rising terrain on both sides, its much better to hug one side so that you have more room to try a 180 if you get boxed in.  Also, the instructor said to fly at reduced speed, to minimize turn radius if you really need to make that turn and GTFO.

 

49 minutes ago, Buckaroo said:

Remember awhile back when the Icon engineer and his passenger entered a box Canyon and stall spun and were killed trying to exit? 

If you entered a canyon that turned out to be a trap how would you handle the 180 in your CT? In Montana we have thousands of these potential traps that sneak up on any mountain flying pilot. 

So how would you handle a safe exit? Lets say you enter at cruise with -6 flaps. A Chandelle? A hard g 180? Slow down and apply 15 of flaps followed by a as needed turn? Ideas??

 

I spend 1/2 my time in such canyons, our route home up the Kern River yesterday really freaked my girlfriend out because we were boxed in for 1/2 hour of cruising.

You can see our view up the Kern River drainage from ~12,000 and climbing. Every way out except the 180 is a big climb.

Because its the Sierra and not Idaho the last thing I do is exit at a slow speed.  There are lots of ways to turn a CT on a dime, my preferred is a wing over entered at 95kts IAS.  

I was in the coastal mountains yesterday and the air was lousy but it was buoyant so my need for speed went away in those canyons.

 

Given your list I would pick a modified Chandelle for a goto that I set a minimum speed for but won't be needed because nose down steep turns without loading the wings seem effortless.

 

Edit:  The fatality you refereed to was a canyon entered into from a body of water and done at a slow speed.  He began out of options. That scenario called for speed while lacking altitude for an exit.  If the Canyon is rapidly rising then you have altitude to loose on your  exits and they become simpler.  If you don't have that altitude to loose speed is mighty handy, with it you will have multiple options.  If you have a passenger they should be freaking out long before it becomes critical if you have good/normal speed.  At min speed the closing rate won't be scary, like in the above mention fatality.

In a nimble CT speed produces a closing rate that causes you to do something while there is plenty of time. Slow can be tricky with drift and shear and downdrafts.

My best advice is this:  In your CT if the canyon flight is deteriorating in exit options and you find your speed decaying then either put your nose back down or get out now before it gets more critical.  

59c6e71e9084a_KernRiver.thumb.jpg.0b37858383dbff5ad1fd16900ab8fe17.jpg

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Buckaroo   

Two great responses thanks! What about flaps settings and speeds? I agree a wing over with low wing loading and minimum g’s is a good thing if you have the altitude! Accelerated stalls are the killer! I would almost think a slow down to say 70 with 15 flaps and a non g wing over would get you around in the shortest distance! This only in non downdraft conditions. 

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Flap setting is absolutely negative six not zero and for me speed is at least 90kts indicated

If you get the chance to do some wing overs in your CT you will see right away that you don't need any room at all to turn around.

Its true that slow is another way to decrease your radius, didn't work in the case you brought up.

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Another bit of thinking is that your CT can descend at an extremely steep angle. Slipping with flaps is effective enough to often provide and option that avoids a lower down  tighter turn to the runway.  It can likely provide the matching steep climb out as well, get to know it.

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3 hours ago, Ed Cesnalis said:

Flap setting is absolutely negative six not zero and for me speed is at least 90kts indicated

If you get the chance to do some wing overs in your CT you will see right away that you don't need any room at all to turn around.

Its true that slow is another way to decrease your radius, didn't work in the case you brought up.

If I saw I was about to potentially get boxed in with insufficient climb performance to escape, I'd slow to 80kt.  You can easily make a 2g+ turn at that speed without stall being a problem, and your turn radius is significantly reduced.  Plus if you decide to execute your wingover, you gain less speed in the dive, meaning less vertical speed needed.

That is one thing about the wingover that needs discussion -- yes, it takes very little *horizontal* space  to execute, but it requires significant *vertical* space.  You'll use up several hundred feet of altitude you might not be able to spare if the ground below you is rising toward the "box".  Just a consideration, each situation is different.

Also,  if none of the above are possible, you could attempt a minimum speed crash landing.  Chop the throttle, turn away as best you can, pitch up, and get the airplane as close to stall speed (without exceeding it, stalls kill here!) as you can before impact.  This will make the impact as survivable as possible.  I would not want to do this is in a Centurion at 75-80kt, but the ~40kt stall speed of the CT makes it an option you could walk away from.

And of course, there is the parachute.  If you really see you are NOT going to make the turn/wingover, and have 3-5 seconds left, it's a great option.

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50 minutes ago, FlyingMonkey said:

If I saw I was about to potentially get boxed in with insufficient climb performance to escape, I'd slow to 80kt.  You can easily make a 2g+ turn at that speed without stall being a problem, and your turn radius is significantly reduced.  Plus if you decide to execute your wingover, you gain less speed in the dive, meaning less vertical speed needed.

That is one thing about the wingover that needs discussion -- yes, it takes very little *horizontal* space  to execute, but it requires significant *vertical* space.  You'll use up several hundred feet of altitude you might not be able to spare if the ground below you is rising toward the "box".  Just a consideration, each situation is different.

Also,  if none of the above are possible, you could attempt a minimum speed crash landing.  Chop the throttle, turn away as best you can, pitch up, and get the airplane as close to stall speed (without exceeding it, stalls kill here!) as you can before impact.  This will make the impact as survivable as possible.  I would not want to do this is in a Centurion at 75-80kt, but the ~40kt stall speed of the CT makes it an option you could walk away from.

And of course, there is the parachute.  If you really see you are NOT going to make the turn/wingover, and have 3-5 seconds left, it's a great option.

I'm producing about 30 images a week and half of them require an escape maneuver.  Often the image I use was captured during the escape.

I've been practicing wing-over canyon escapes in the highest mountains in the 48 states for 30 years. Canyons do rise towards the box, almost all of the time but it doesn't cost you any altitude once you initiate your climb.

Here's a reality you wouldn't expect, Canyon's are often parallel to canyons. If you initiate with a climb you can decide if you want to do a 180 degree swap ends return on the reciprocal heading or just as  likely a more gentle  turn has you descending in the next canyon over doing a less demanding maneuver and allowing the wind to drift you if it wants.  The photo shows parallel canyons the terminate and can be escaped cross canyon or on a reciprocal but not ahead but I would not want to do it slow.  We have experience getting rescue helicopters into this area and the winds require a strategy.

Escaping is and should be intuitive and you adjust to the buoyancy of the air, the steepness of the terrain and the nature of the turbulence and drift to know in what positions you are safe and when  you are vulnerable and if a slow turn is reasonable. The discussion about the minimum speed turn has its place and maybe Montana is one of them I'm not that familiar. 

Speed and Altitude are our friends, I generally refuse to run out of both and then do a critical maximum performance maneuver (slow exit turn).  In a CT the extra speed needed for easy exiting just feels right anyway.

Dragtooth.jpg

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ct9000   

If you are flying on the down wind side at reduced speed say 80-90kt when you pull into a steep turn with wings near vertical, the effect of the increasing headwind will tighten the radius of the turn to the extent that you need little room at all. 

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Another minor or major consideration, depending on your point of view:  a wingover requires a bank of over 60 degrees, which makes it an aerobatic maneuver.  Each time you do one you are violating the FARs by exceeding the operating limits of the airplane.  

I would not even hesitate over that in a true emergency, but intentionally flying up a box canyon and executing a wingover as an escape is...”not sanctioned” by the FARs.

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2 hours ago, FlyingMonkey said:

Another minor or major consideration, depending on your point of view:  a wingover requires a bank of over 60 degrees, which makes it an aerobatic maneuver.  Each time you do one you are violating the FARs by exceeding the operating limits of the airplane.  

I would not even hesitate over that in a true emergency, but intentionally flying up a box canyon and executing a wingover as an escape is...”not sanctioned” by the FARs.

I'm not sure about the 60 degree requirement. There is a zero bank 'military wing over' that's very cool. In either event I generally do get inverted for a bit and on a 'Military' at least your pitch attitude is far beyond 30 degrees.  

Executing a wing over in a real emergence creates no violation but practicing it does.  At this point in my career I can do them in my sleep.

The way I do it in a CT is incrementally. Stage 1 is to climb and evaluate. Stage 2 is to decide if a legal Chandelle is the way to finish or if there is no room and a wing over is needed.  You can legally practice all but the wing over part and both maneuvers begin at a high energy level and a zoom climb.

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