Teach primary students Steep Spirals?

AggieMike88

AggieMike88

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The original "I don't know it all" of aviation.
Question came up during the “teach the commercial student” part of my CFI class as we were being shown to teach steep spirals

Should Steep spirals be taught to primary students, not just commercial?
 
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I don't see the need. KISS.

Might be fun to do an hour or two of advanced maneuvers post-checkride if the student expressed an interest, though my preference might be the chandelle to start.
 
Meh I don’t really see a reason to. During my commercial training I thought it was a bit useless. Turns about a point and simulated engine outs kinda cover the purpose of a steep spiral too. As already mentioned Chandelle would be a more useful skill set.
 
I remember doing it once. My CFI talked me through it. It was a "let's do this" vs "learn how to do this" type of deal, there were no commercial standards being applied.
 
I think it's a useful exercise since it demonstrates how easy recovery is by simply rolling level and letting the redirected lift vector solve the problem.
 
I'll offer a contrary opinion: Steep spirals are an integral part of emergency landing skill set.
 
Dan Thomas said:
A VFR pilot flying into IMC can end up in a steep spiral without knowing it. He pops out of the cloud base and see the ground coming at him so he does the wrong thing: pulls back. And the wings come off or the stab fails downward. Levelling the wings first is the key to survival.

It shows up in Lesson #6 of Canada's Flight Instructor Guide, well before solo. https://www.tc.gc.ca/eng/civilaviation/publications/tp975-menu-5494.htm#part-iii-lesson-plans
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While I agree that is necessary training, it is covered under upset recovery. The purpose of the Steep Spiral in the commercial maneuvers is to lose large amounts of altitude while remaining above an intended landing spot.
 
So, here's the AFM's first paragraph about the steep spiral (with my emphasis):

The objective of the steep spiral is to provide a flight maneuver for rapidly dissipating substantial amounts of
altitude while remaining over a selected spot. This maneuver is especially effective for emergency descents or landings.​

Let's compare that to the emergency descent private pilot task:
An emergency descent is a maneuver for descending as rapidly as possible to a lower altitude or to the ground for an emergency landing.​

Biggest problem seems to be their similarity.
 
Dan Thomas said:
A VFR pilot flying into IMC can end up in a steep spiral without knowing it. He pops out of the cloud base and see the ground coming at him so he does the wrong thing: pulls back. And the wings come off or the stab fails downward. Levelling the wings first is the key to survival.

It shows up in Lesson #6 of Canada's Flight Instructor Guide, well before solo. https://www.tc.gc.ca/eng/civilaviation/publications/tp975-menu-5494.htm#part-iii-lesson-plans
Click to expand...
Yeah, but the inadvertent steep spiral loss of control due to loss of situational awareness in the clouds is not the gentle visual glide over a spot transitioning to a normal pattern and landing which makes up the commercial steep spiral.
 
Read ACS page 51 Emergency Descent.

The Task requires “Use bank angle between 30° and 45° to maintain positive load factors during the descent.”
 
Clip4 said:
Read ACS page 51 Emergency Descent.

The Task requires “Use bank angle between 30° and 45° to maintain positive load factors during the descent.”
Click to expand...
Commercial steep spirals are not emergency descents.
 
midlifeflyer said:
Yeah, but the inadvertent steep spiral loss of control due to loss of situational awareness in the clouds is not the gentle visual glide over a spot transitioning to a normal pattern and landing which makes up the commercial steep spiral.
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Didn't say it was, and we didn't teach it that way. It comes early in the PPL so that the student gets a handle on it. PPLs aren't immune to continue VFR into IMC.
 
Dan Thomas said:
Didn't say it was, and we didn't teach it that way. It comes early in the PPL so that the student gets a handle on it. PPLs aren't immune to continue VFR into IMC.
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Seems kind of implied since you brought it up in a thread discussing Commercial Steep Spirals when you are really talking about unusual attitude and upset recovery training which is taught during ppl training.
 
Dan Thomas said:
Didn't say it was, and we didn't teach it that way. It comes early in the PPL so that the student gets a handle on it. PPLs aren't immune to continue VFR into IMC.
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I guess I misunderstood. Sure seems you are describing a scenario which has nothing to do with the commercial maneuver.
 
Grum.Man said:
While I agree that is necessary training, it is covered under upset recovery. The purpose of the Steep Spiral in the commercial maneuvers is to lose large amounts of altitude while remaining above an intended landing spot.
Click to expand...

midlifeflyer said:
Yeah, but the inadvertent steep spiral loss of control due to loss of situational awareness in the clouds is not the gentle visual glide over a spot transitioning to a normal pattern and landing which makes up the commercial steep spiral.
Click to expand...

My instructor showed it to me and I'm glad he did.

Not long after passing my primary checkride, I found myself boxed in by clouds while at 9500msl. I looked down, and the hole was directly under me and by luck I happened to be over a good sized airport (DYR). I tell myself that's my lifeboat, don't leave your lifeboat without a good plan. As I start spiraling down towards the airport, the box of clouds becomes a box of thunderstorm, with visible bolts of lightning around me. So as I'm spiraling, I'm on radio trying to get some advice regarding the storm.

And of course I lose awareness a bit, and when I finally look at the instruments, my bank is beyond 45*, airspeed nearing redline, and the VSI at about 1500 down. I got the power off, shallowed the bank, and slowly eased back on the yoke and got things under control, then stayed riveted on the insturments. I got under the clouds at 3000msl, and radio had a recommended vector, so I followed that vector and got outta dodge, leaving the TS behind.

The rest of the way home was flying at 3000 under a deck that was 3500, and nearly constantly talking to radio so I wouldn't blunder into another TS. This was during the days before XM/ADSB weather and radar in the cockpit.

The very next day I called my CFI and started IR training.
 
Bill Jennings said:
My instructor showed it to me and I'm glad he did.

Not long after passing my primary checkride, I found myself boxed in by clouds while at 9500msl. I looked down, and the hole was directly under me and by luck I happened to be over a good sized airport (DYR). I tell myself that's my lifeboat, don't leave your lifeboat without a good plan. As I start spiraling down towards the airport, the box of clouds becomes a box of thunderstorm, with visible bolts of lightning around me. So as I'm spiraling, I'm on radio trying to get some advice regarding the storm.
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That's a good thing and it was indeed a steep spiral and not an inadvertent loss of control due to loss of situational awareness in the clouds (which is not the commercial steep spiral).

I think you would have accomplished the same with a private pilot level emergency descent.
 
midlifeflyer said:
I think you would have accomplished the same with a private pilot level emergency descent.
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Maybe, at the time my only thought was "I have to descend fast in this little box..."

I didn't know how long the window would stay open to get down. It was a good learning experience, for sure, and shows how quickly things can go to crap if you don't keep an eye on the instruments.
 
Sure, they are fun.

I also am a fan of spin training and falling leaf stalls and tailwind landings pre solo
 
Few important lessons there if they are ready for them.

Getting out of a spiral without ripping with wings off.
Turning really steep without stalling (AOA lesson) or overspeeding
Things not to do with passengers
How to clear your ears really well.
 
You can teach a student pretty much anything you feel you need to that's legal and beneficial, but beware of adding too much extra to the curriculum. For starters, students have access to freely available syllabus examples and if you start doing too much that's not required and end up spending 5-10 more hours, that can bite you from a standpoint of them wanting to finish.
 
I'm unclear how this is different from a spiraling emergency descent, unless it's because of a minimum number of turns for the commercial maneuver. My CFI had me do a steep spiral descent, approximately 40 degrees of bank and pitched for an airspeed in the yellow arc, when simulating an engine fire. My DPE ran the same scenario on the PPL checkride. During unusual attitudes, my CFI also put me into a steep spiral several times and had me recover.

Do real engine fires always happen over airports, the way simulated ones seem to? ;)
 
Half Fast said:
I'm unclear how this is different from a spiraling emergency descent, unless it's because of a minimum number of turns for the commercial maneuver. My CFI had me do a steep spiral descent, approximately 40 degrees of bank and pitched for an airspeed in the yellow arc, when simulating an engine fire. My DPE ran the same scenario on the PPL checkride. During unusual attitudes, my CFI also put me into a steep spiral several times and had me recover.

Do real engine fires always happen over airports, the way simulated ones seem to? ;)
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If you have a fire, the emergency descent (spiral) is used to extinguish the fire with excess O2 and get to terra firma quickly. Airspeed in the yellow.

The steel spiral commercial maneuver is done at best glide airspeed. Same 45 degree bank.

They are different terms / maneuvers.
 
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I was required to do it before my CFI would let me come back to the field one day .... he was like you gotto do a couple of them, else we are sitting here and will glide to that cornfield when we run out of gas ....
 
texasclouds said:
If you have a fire, the emergency descent (spiral) is used to extinguish the fire with excess O2 and get to terra firma quickly.

The steel spiral commercial maneuver is done at best glide airspeed. Same 45 degree bank.

They are different terms / maneuvers.
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Flaps.
 
It is a good maneuver to learn for practical use, as well as for aircraft control. I don't see why you wouldn't do it. I learned power off landings, and not just 180s, during my PPL.
 
Clip4 said:
Read ACS page 51 Emergency Descent.

The Task requires “Use bank angle between 30° and 45° to maintain positive load factors during the descent.”
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The AFH, on the other hand, says to use the bake “when initiating the descent”. Once the descent is established, 1 g straight ahead is still a positive load factor.
I think the ACS writers misinterpreted the statement.
 
FastEddieB said:
Curious how this works.

I’m thinking of what happens when I hit my brush pile with a leaf blower.
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Are you implying you don’t agree that too high of an O2 to fuel/heat ratio would inhibit fire? Or that the proposed method probably would not work in an aircraft?
 
texasclouds said:
Are you implying you don’t agree that too high of an O2 to fuel/heat ratio would inhibit fire? Or that the proposed method probably would not work in an aircraft?
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Not sure. Just observing that any time I hit a fire with a lot of air, it flared up. Is there some critical velocity where it it extinguishes a fire? A source would be nice.
 
FastEddieB said:
Not sure. Just observing that any time I hit a fire with a lot of air, it flared up. Is there some critical velocity where it it extinguishes a fire? A source would be nice.
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Light a candle then go blow it out using high velocity air expelled from your lungs.

The AFM for the 172SP mentions the emergency descent’s use to put out an in-flight engine fire (along with shutting off fuel valve and mixture).

I reckon it would take a Tim Taylor Binford 3000 Leaf Blower to extinguish a brush pile fire.

19FF3615-A1E3-40AC-8F96-76008121B745.jpeg
 
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FastEddieB said:
Not sure. Just observing that any time I hit a fire with a lot of air, it flared up. Is there some critical velocity where it it extinguishes a fire? A source would be nice.
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Have you ever blown out a match or a candle, or had trouble lighting one in the wind?
 
MauleSkinner said:
The AFH, on the other hand, says to use the bake “when initiating the descent”. Once the descent is established, 1 g straight ahead is still a positive load factor.
I think the ACS writers misinterpreted the statement.
Click to expand...

The task says to maintain a positive G loading. If 1G was acceptable there would be no need for the reference.
 
Clip4 said:
Read ACS page 51 Emergency Descent.

The Task requires “Use bank angle between 30° and 45° to maintain positive load factors during the descent.”
Click to expand...

So what does that mean? The only time you might come close to not maintaining positive load factor is in the push over into the descent. So my (and others) best interpretation is to roll into the descent but then the turning is optional to get to your desired landing area. Notice it does not say "maintain a bank"

Brian
CFIIG/ASEL
 
Clip4 said:
The task says to maintain a positive G loading. If 1G was acceptable there would be no need for the reference.
Click to expand...

1g is positive, how is that not acceptable?
 
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