Backcountry Pilot

[Mongo offline]

I was out messing around today (it was beautiful) and I tried a bunch of canyon turns.
Wow, you can turn 180 on a dime, how many of you have tried this?

[River rat offline]

What do you call a canyon turn? A hammerhead?

[Mongo offline]

Reduce power
Raise nose to Vfe
Begin coordinated turn to almost 90 deg bank reducing back pressure to zero as bank increases
apply flaps (should be in by about 20 degrees of bank)
apply full power
as you reduce bank angle back to zero increase back pressure and reduce power so as to stay below Vfe
Remove flaps
Smile

It is a bit like being a one legged man in an a%% kicking contest, but man does it rotate, and with almost no altitude lost...

Could be a life safer one day.

[Zzz]

Some good info on that topic:

http://www.backcountrypilot.org/forum/viewtopic.php?f=6&t=1019

I did practice those during the checkout in my plane and it is amazing how tight a radius you can carve, and how hard you have to push on the stick once you begin the turn if you're trimmed for a normal approach.

[Mongo offline]

Cool
Thanks Zane

[EZFlap offline]

The "canyon turn" is a great maneuver that makes full use of Cessna's big flaps, however it does add a lot of drag. So if you have to use that maneuver at high DA or on hot days in the back country, realize that you will have a LOT less total "energy" left in the aircraft when you're done.

So you may get your 180 degree reverse ane be pointed out of the canyon, but you may not have enough flying speed to stay in level flight on your way out.

The problem I see with the "canyon turn" maneuver is that it is dependent on having enough airspeed at the beginning to be able to lose all that energy in the turn and still have enough speed on the way out. The problem with tHIS is that as you enter the canyon and start to realize you are in trouble, the first thing most of us would do is try to climb out, which means we start losing speed. So by the time we wake up and say "Oh S**T I better use that "canyon turn" maneuver!!!" the airspeed may already be down to best climb speed.

Although I have not been in the position to be forced to use this maneuver yet, I would bet that the hammerhead stall maneuver is equally valid under many circumstances.

[Mongo offline]

You should only use the most efficient flap angle for your plane, not the max angle.
This will be around the same angle as your ailerons will deflect maybe a bit more, 10-20 degrees not 30-40.
Remember flaps (camber) only add lift to a point, then mostly just drag, so as to steepen the approach angle.

Any procedure which is practiced a lot (such as stall/spin), will become second nature and be your first instinct, not just a yank on the yoke(hopefully ).

[gbflyer offline]

When poking around in tight places, slowed down with half flaps is a good idea. We are typically in this situation because the ceiling is low, so any climbing wing over maneuver would result in going IMC, which makes it a bit more sporty. Our AGL altitude is generally low and as a result any modified split - s type deal would result in a crater and wouldn't be practical. With the slow/flaps configuration, our little airplanes turn around quickly and safely. Fly along one side or the other with enough visibility to see the other side, always leaving yourself a way out. We can argue that one shouldn't be there to start with, but this way minimizes the risk we've already committed to.

Personally, I am a firm believer in staying out of canyons, especially on those high DA or poor vis./low ceiling days and certainly if I'm in an unfamiliar place. There's enough man - made hazards in a lot of them to give me nightmares. Play around with it long enough and it will bite you hard, guaranteed. Remember the weather is always clear and a million the first day of the search.

gb

[jomac offline]

all very good points, gb. high da and winds in the canyons of idaho is quite a deadly combination. makes for one reason we stacked up so many birds here this year...as for canyon turns, yours is a good recomendation. each bird is different, i use full,30%, full power, 65 on the speed, no drop in altitude, few feet max. allows a complete 180 in less than 100', no neg load. it is fun and effective and can help u in a tight spot...

[shortfielder offline]

I'll suggest that not everyone does a canyon turn as desribed above. I know I don't. Do some readin, talk to others w/experience, get some instuction, whatever way you choose, but don't just go into a canyon and learn. Get some altitude and practice out in the open, maybe next to a hill, turning away from the hill.

The last place I want to be is in a canyon w/flaps on, slow, in a 90 degree bank.

My personal technique, Scenario abbreviated version) flying up a canyon, climbing to get out, narrowing, obvious that I am not going to be able to out climb terrain, IAS 60 kts, Begin the turn to 30-40 degrees, bring in full flaps, maintain the 60,and around we go. Level the wings, and go somewhere else.

I also think it's good to practice this in both directions. Works well, pretty benign manuever, so even if you are dealing with some turbulence, you should be somewhat comfortable in an uncomfortable situation.

Gary

[n6zt offline]

For those of you who don't read supercub.org, it is another great aviation site. You might want to read the following thread....especially the reply by MTV. http://www.supercub.org/phpbb2/viewtopic.php?t=19680
Jim

[Zzz]

The practice version of the "canyon turn" I was taught was to enter from an approach scenario, which has you low on energy to begin with:

You're descending into a one-way airstrip with maybe a blind approach, and once you're close enough to see the giant deadfall or fifth-wheel blocking the already short strip, it's too late to do a straight-out go around. The only option is to make a 180.

For the Cessna 170:
From 70 mph IAS, go full power, level off, full flaps, 60 degree bank, maintain 80 mph IAS. It requires a heavy hand on the stick countering the aircraft's tendency to pitch up with full flaps out and full power. Starting the turn from the far side of the canyon to give maximum room for turn radius is critical as well.

I've only done them a few times, so I'm no expert obviously. It's good to know what can be done.

[shortfielder offline]

There will probably be a lot of response/theories here. My main resaon for posting was to stop someone without much experience from going up a canyon.getting slow, banking 90 degrees, and pulling the flaps on.

Good point by Zane to maximize your room for manuevering by getting as close to the canyon wall as you are cofortable with,before you start the manuever.

[Portage Creek offline]

Practicing out in the open blue is not the answer. Get in a valley ( not a canyon yet) and practice. Get a technique that works for you and you feel automatic with . Do it and try variations. When the time comes you may not be able to use your favorite move.

Then get into something tight. Something that still has room in good conditions, but would be tight in bad. Find out how well it works. Practice so when you need it you can perform with confidence.

I have my favorites and they have been mentioned here. Get your favorite with variations. Practice and have fun.

GR

[58Skylane offline]

There will probably be a lot of response/theories here. My main resaon for posting was to stop someone without much experience from going up a canyon.getting slow, banking 90 degrees, and pulling the flaps on.

Good point by Zane to maximize your room for manuevering by getting as close to the canyon wall as you are cofortable with,before you start the manuever.

All good points here. But coming from a newbie, wouldn't it be smart to try these manuevers with a CFI first? No way am I brave enough or stupid enough to try these manuevers on my own with out proper instruction from a capable CFI.

Although, common since tells me first not to get myself in a situation where a canyon turn, chandelle, hammerhead, etc is your only life or death manuever out of trouble.

[Mongo offline]

58skylane

You need to get in a Citabria or Decathlon and do so aerobatic training you would love it.
There is nothing like getting out of an inverted spin when you botch a loop, gets pretty exciting.

[Oregon180 offline]

I think this is a case where one hour of instruction with a good mountain/canyon flying instructor is worth the reading of a thousand forum posts...

What I mean by that is that the canyon turn is a potentially life-saving and conceptually simple maneuver that's hard to describe well in writing and the procedure will be somewhat different for every type of aircraft.

[Mongo offline]

Were on a points system, I must still be in single digits.

[58Skylane offline]

58skylane

You need to get in a Citabria or Decathlon and do so aerobatic training you would love it.
There is nothing like getting out of an inverted spin when you botch a loop, gets pretty exciting.

I'd like to. There's plenty of them at Caldwell.

[Oregon180 offline]

Were on a points system, I must still be in single digits.

Hey Mongo, I think you misunderstood my post. All I meant is that if someone wants to learn how to do canyon turns, it's probably more efficient to just go out with an instructor. Certainly didn't mean anything against you or anyone else here.