Emergency Descent

[ScottinIowa]

I've got my PPL ride in a couple days and was doing some cruising online to make sure I haven't missed any small details and I ran into a few people discussing the ED procedure. Now I was taught by two different CFI's to use the no flaps, speed to top of green arc, 30-45 degree bank method. Others are suggesting slowing to Vfe, full flaps, then descend. I'm a bit conflicted here. I think if my examiner declares smoke in the cockpit or engine fire and I pitch up, it's probably not going to go well. Thoughts?

 

[EdFred]

What does the AFH say?

 

[RyanB]

Think about it, if you’re wanting to get down on the ground as fast as possible are you really going to want to SLOW the aircraft down and put in flaps right away? No.

Top of Green Arc and fly your best forward airspeed until the landing site is made and then transition to slowing the aircraft. Depending on what you fly will be the deciding factor on when to do this.

 

[ScottinIowa]

What does the AFH say?

AFH says use flaps/gear per the manufacturer. There is no ED procedure for the 140 I fly.

 

[ScottinIowa]

Think about it, if you’re wanting to get down on the ground as fast as possible are you really going to want to SLOW the aircraft down and put in flaps right away? No.

Top of Green Arc and fly your best forward airspeed until the landing site is made and then transition to slowing the aircraft. Depending on what you fly will be the deciding factor on when to do this.

And that's what makes sense to me too, but others and the AFH seem to suggest flaps is the best method. Seems odd to me. I'm going to bring this up with my DPE and see what he prefers.

 

[RyanB]

And that's what makes sense to me too, but others and the AFH seem to suggest flaps is the best method. Seems odd to me. I'm going to bring this up with my DPE and see what he prefers.

I don’t think there’s any one size fits all answer if it were a real ED scenario. You’re going to do what you have to do, to get the airplane where it needs to be.

I suppose the argument for adding flaps right away is that it will provide a steeper decent rate without causing an increase in airspeed, and that may work...if the landing site is within a short distance from you. For me, I’m going to delay adding flaps until a bit later.

 

[ScottinIowa]

I don’t think there’s any one size fits all answer if it were a real ED scenario. You’re going to do what you have to do, to get the airplane where it needs to be.

I suppose the argument for adding flaps right away is that it will provide a steeper decent rate without causing an increase in airspeed, and that may work...if the landing site is within a short distance from you. For me, I’m going to delay adding flaps until a bit later.

You could also argue that during a check ride if you're doing maneuvers at 3000AGL or less, you wouldn't want to hurl towards the ground at the top of the green arc. Flaps might be the better option assuming you'll be putting it down in a field within a couple minutes.

 

[RyanB]

You could also argue that during a check ride if you're doing maneuvers at 3000AGL or less, you wouldn't want to hurl towards the ground at the top of the green arc. Flaps might be the better option assuming you'll be putting it down in a field within a couple minutes.

Again, there isn’t a one size fits all answer, as it’s going to greatly depend on the situation.

I agree that it might be a good topic of conversation to bring up with your DPE.

 

[Tantalum]

What does the AFH say?

+1

Not sure on what you are flying, but my POH for the Cirrus has the plane clean, power to idle, and pitch for Vne.. unless "significant" turbulence is expected, then Vno. So it sounds like your CFI is right.

People tend to like the idea of flaps because it adds drag.. but think about it in your head. Say you are cruising along at 150 knots and need to descend in an emergency.. you are going to have to first slow to flap range, then point the nose down, but keep the plane within the flap range. Seems like you are limiting yourself and will be fighting the plane, and the "high lift devices" as you race to get down in a burning airplane. By the time the 30 or 45 seconds have gone by as you slow down and extend the flaps you could have already probably lost 700 feet by just going to idle and pointing the nose down. Plus, with the amount of just "natural drag" the typical 172 or Cherokee has it's pretty hard to get to the top of the green (or yellow ) arc, especially with the power at idle.. you'll be pretty much staring at the ground

 

[midwestpa24]

If you are suspecting an engine fire, maximum airspeed is usually recommended to attempt to blow out the fire.

I don't know the right answer here though, I've been taught both ways over the years. Not sure I've ever seen a consensus on which is faster/preferred.

 

[Grum.Man]

I agree that every situation and aircraft is different. In my airplane I am going to slow to gear and flap speed and then make the decent. I can get down much faster that way than with the airplane clean.

 

[Tantalum]

I'm going to bring this up with my DPE and see what he prefers.

By the way, the AFH is just a handbook.. I would go by what it says in the POH itself, which the manufacturer has calculated and prescribed and is FAA approved. In my experience this will be clean and top of green (or yellow) arc.

If you do not have an emergency descent procedure, as you indicate you do not.. then why not try them both with your CFI on board? Go up to 6K and get into cruise configuration, etc... and then try it both ways and time which one gets you to 3K faster. Going to idle and pitching the nose down to top of green arc. Or first slowing down, extending the flaps, and then pitching down to top of flap range. My money is on the former giving you faster actual descent rate (but you'll cover more mileage over the ground.. which can be a good or a bad thing.. however if you are in a 30-45 degree bank and spiraling then you'll be pretty in one spot anyway).. Might be a fun way to kill an hour with your CFI and make you that much more in tune with your machine

 

[tspear]

Depends on why the ED, and the weather.
If the weather is rather bumpy, slowing to drop gear, flaps, and brakes can give you a higher descent rate than Vno. If smooth, generally just under Vne is the quickets.
However, in all cases, check the manual and see what works for the plane. If nothing in the manual, it is a good excuse to go fly and see what the difference is.

Tim

 

[Clip4]

Here is the Airplane Flying Handbook says:

Emergency Descents
An emergency descent is a maneuver for descending as rapidly as possible to a lower altitude or to the ground for an emergency landing. [Figure 17-6] The need for this maneuver may result from an uncontrollable fire, a sudden loss of cabin pressurization, or any other situation demanding an immediate and rapid descent. The objective is to descend the airplane as soon and as rapidly as possible within the structural limitations of the airplane. Simulated emergency descents should be made in a turn to check for other air traffic below and to look around for a possible emergency landing area. A radio call announcing descent intentions may be appropriate to alert other aircraft in the area. When initiating the descent, a bank of approximately 30 to 45° should be established to maintain positive load factors (G forces) on the airplane.

https://www.aopa.org/news-and-media...raining-magazine/checkride-emergency-descents

For those who say just chop the power, keep the flaps up and go, what about Va? Below Va most training aircraft will descend more rapidly with flaps.

 

[Timbeck2]

Another thing is to decide with your DPE before the flight if you are to follow the checklist to a tee. My CFI and I had only simulated turning the master off in training flights. The DPE expected me to turn the master off (then contact ATC and declare an emergency...yeah, I know) which I simulated and I failed that portion of the check ride.

 

[Tantalum]

I've never seen this written in a POH, but one of my CFIs had me do a pretty, um, robust maneuver with a full flaps, and the strongest slip you could get out of the plane with full rudder.. at the top of the flap range to demonstrate a "real life" emergency descent. This was a while ago in a PA28-161.. I want to say we get somewhere in the 1,500 to almost 2,000 fpm range doing this. His logic was that if your engine is on fire then you'll want to get down as soon as possible, you won't necessarily worry about damaging or fatiguing a part doing this. Also, if the engine is on fire you'll want to be blowing that fire AWAY from the cabin.. doing a hard slip will keep the fire blowing sideways (note, he demo'd this and we didn't hold it for longer than a few seconds to demonstrate what a monster descent rate you could get by doing this)

Speaking hypothetically, it sort of makes sense.. and frankly if I ever am in "holy crap I am on fire and might die!" situation then obviously CAPS is out of the question, then I'd probably do the same thing. Drop the flaps, and slip the living daylights out of it.. at that point who cares if you bend a flap track fitting or whatever

 

[EdFred]

If you solely want the fastest way down that is via a spin.

 

[DaleB]

When I took my checkride the only rapid/emergency descent I had been taught was slow to just above stall speed and do a full deflection slip. The examiner said it would work, and in case of an engine fire it might keep the smoke away from the windscreen so you might be able to see better. Then he showed me a 60 degree bank with power at idle, not at Vne but well into the yellow arc. Much faster.

 

[Skip Miller]

You are forced to choose between two basic maneuvers: Diving down in a clean configuration, and slowing down, putting out all the laundry to dirty up your airframe. Be prepared to discuss the pros and cons of each and why you chose the one you elected. And what would have made you choose the other method. That's a pass right there.

-Skip

 

[Stickman]

Emergency descent is primarily a maneuver for pressurized high performance aircraft. The main reason you would do one is for a sudden uncontrolled pressurization loss. The purpose (and certification requirement) is to get from a high altitude cruise to an altitude with a breathable atmosphere in as short a time span as possible.

The main reason there is a discussion about high speed vs. slower speed/higher drag descent has to do with structural integrity. When training for a type rating both scenarios are demonstrated. If there is a big hole in the airplane then obviously you don't want to do a descent at MMO/VMO.

A rapid descent in a low performance single would most likely be for a fire or rapidly developing airframe failure (Maybe a propeller failure) in both cases it would completely depend on the situation.

Even Boeing leaves it up to the crew to decide.

 

[Tantalum]

If you solely want the fastest way down that is via a spin

Wasn't that taught a long time ago as a way to get out of inadvertent IMC.. I'm talking Sopwith Camel days?

 

[steingar]

Depends on the airplane. In the Cherokee 140 I used to fly the procedure was just like that other fellow said: power off, flaps in, biggest slip I could manage and down she came. I lost 7K feet on downwind once, no foolin'. But the Cherokee's flap speed and cruise speed weren't terribly different, so it made good sense.

The Mooney I now fly cruises at 160 mph but has a flap speed of about 100. Slowing to flap speed would be nearly nonsensical, if there really is a fire I'll burn up before I hit it. Gear speed is 120, again it will take some doing so slow down to that. Says me point the nose down and get down right now. If the excrement really has hit the air conditioning, I'm not going to be too picky about any of those V speeds either.

Personally, I think the DPE will be more impressed with knowing why we do what we do than with rote memorization of a procedure.

 

[Eric Gleason]

It would be difficult for a DPE to fail you if you follow the procedures in the POH for your airplane.

You could also go out in the plane and try a couple of different procedures and see which works best. When asked to do the maneuver, if your method differs from the POH, you talk the DPE through it and explain why you're doing what you're doing. Unless you specifically fail an ACS item, violate an FAR, or fly the plane outside of its prescribed flight envelope, the DPE is likely to have little to say about it.

Wasn't that taught a long time ago as a way to get out of inadvertent IMC.. I'm talking Sopwith Camel days?

It was. I think people stopped doing that by WW2 or so.

 

[midlifeflyer]

By the way, the AFH is just a handbook..

Yeah, but it's the handbook which is referenced as a source of the maneuvers preformed in the practical test.

@Clip4 left out the rest of the description:

Emergency descent training should be performed as recommended by the manufacturer, including the configuration and airspeeds. Except when prohibited by the manufacturer, the power should be reduced to idle, and the propeller control (if equipped) should be placed in the low pitch (or high revolutions per minute (rpm)) position. This allows the propeller to act as an aerodynamic brake to help prevent an excessive airspeed buildup during the descent. The landing gear and flaps should be extended as recommended by the manufacturer. This provides maximum drag so that the descent can be made as rapidly as possible, without excessive airspeed. The pilot should not allow the airplane’s airspeed to pass the never-exceed speed (VNE), the maximum landing gear extended speed (VLE), or the maximum flap extended speed (VFE), as applicable.​

It continues on and mentions the in-fire emergency where airspeed is important on the theory that you may create the incombustible mixture and put the fire out.

Some POH contain a procedure for it. Mooney describes both in later M20J models but prefers has both but recommends gear extended but not flaps. Others contain no procedure at all.

The key here is the AFH actually gives excellent advice. Ultimately, you choose the one that's appropriate to the emergency the DPE sets up as a scenario. Engine fire, I'm doing clean at VNE or VNO if not smooth. Sick passenger but conscious? I'm probably going to use a slower speed with flaps extended to increase drag (unless the POH recommends against it). No reason to add terror to the passenger's problems. I suspect modern DPEs are more interested in the thought process involved in selecting which of multiple options to use than in choosing the one they like to see (which I see @steingar just said )

 

[Clip4]

You are forced to choose between two basic maneuvers: Diving down in a clean configuration, and slowing down, putting out all the laundry to dirty up your airframe. Be prepared to discuss the pros and cons of each and why you chose the one you elected. And what would have made you choose the other method. That's a pass right there.

-Skip

Actually, there is not reason to pitch up and slow. Roll into the turn with proper elevator control and the airplane will slow into gear/flap speed quite quickly.

 

[Capt. Geoffrey Thorpe]

I've got my PPL ride in a couple days and was doing some cruising online to make sure I haven't missed any small details and I ran into a few people discussing the ED procedure. Now I was taught by two different CFI's to use the no flaps, speed to top of green arc, 30-45 degree bank method. Others are suggesting slowing to Vfe, full flaps, then descend. I'm a bit conflicted here. I think if my examiner declares smoke in the cockpit or engine fire and I pitch up, it's probably not going to go well. Thoughts?

Doing something for the absolute first time when the DPE is in the other seat is probably not the best idea.

So, try it ahead of time. You could even try it twice - once with and once without flaps to see which gives you biggest number in the VSI - then you can explain to the DPE why you chose the method you did instead of just saying "some guy told me". You may find that a rudder to the floor, yoke way forward and hard opposite the rudder, slip gets you down the fastest and would keep the smoke from an under cowl fire away from the windscreen.

 

[Clip4]

Yeah, but it's the handbook which is referenced as a source of the maneuvers preformed in the practical test.

@Clip4 left out the rest of the description:

Emergency descent training should be performed as recommended by the manufacturer, including the configuration and airspeeds. Except when prohibited by the manufacturer, the power should be reduced to idle, and the propeller control (if equipped) should be placed in the low pitch (or high revolutions per minute (rpm)) position. This allows the propeller to act as an aerodynamic brake to help prevent an excessive airspeed buildup during the descent. The landing gear and flaps should be extended as recommended by the manufacturer. This provides maximum drag so that the descent can be made as rapidly as possible, without excessive airspeed. The pilot should not allow the airplane’s airspeed to pass the never-exceed speed (VNE), the maximum landing gear extended speed (VLE), or the maximum flap extended speed (VFE), as applicable.​

It continues on and mentions the in-fire emergency where airspeed is important on the theory that you may create the incombustible mixture and put the fire out.

Some POH contain a procedure for it. Mooney describes both in later M20J models but prefers has both but recommends gear extended but not flaps. Others contain no procedure at all.

The key here is the AFH actually gives excellent advice. Ultimately, you choose the one that's appropriate to the emergency the DPE sets up as a scenario. Engine fire, I'm doing clean at VNE or VNO if not smooth. Sick passenger but conscious? I'm probably going to use a slower speed with flaps extended to increase drag (unless the POH recommends against it). No reason to add terror to the passenger's problems. I suspect modern DPEs are more interested in the thought process involved in selecting which of multiple options to use than in choosing the one they like to see (which I see @steingar just said )

Yeah, but it's the handbook which is referenced as a source of the maneuvers preformed in the practical test.

@Clip4 left out the rest of the description:

Emergency descent training should be performed as recommended by the manufacturer, including the configuration and airspeeds. Except when prohibited by the manufacturer, the power should be reduced to idle, and the propeller control (if equipped) should be placed in the low pitch (or high revolutions per minute (rpm)) position. This allows the propeller to act as an aerodynamic brake to help prevent an excessive airspeed buildup during the descent. The landing gear and flaps should be extended as recommended by the manufacturer. This provides maximum drag so that the descent can be made as rapidly as possible, without excessive airspeed. The pilot should not allow the airplane’s airspeed to pass the never-exceed speed (VNE), the maximum landing gear extended speed (VLE), or the maximum flap extended speed (VFE), as applicable.​

It continues on and mentions the in-fire emergency where airspeed is important on the theory that you may create the incombustible mixture and put the fire out.

Some POH contain a procedure for it. Mooney describes both in later M20J models but prefers has both but recommends gear extended but not flaps. Others contain no procedure at all.

The key here is the AFH actually gives excellent advice. Ultimately, you choose the one that's appropriate to the emergency the DPE sets up as a scenario. Engine fire, I'm doing clean at VNE or VNO if not smooth. Sick passenger but conscious? I'm probably going to use a slower speed with flaps extended to increase drag (unless the POH recommends against it). No reason to add terror to the passenger's problems. I suspect modern DPEs are more interested in the thought process involved in selecting which of multiple options to use than in choosing the one they like to see (which I see @steingar just said )

Actually, here is the full section I quoted Airplane Flying Handbook Emergencies Page 17-6.

Emergency Descents
An emergency descent is a maneuver for descending as rapidly as possible to a lower altitude or to the ground for an emergency landing. [Figure 17-6] The need for this maneuver may result from an uncontrollable fire, a sudden loss of cabin pressurization, or any other situation demanding an immediate and rapid descent. The objective is to descend the airplane as soon and as rapidly as possible within the structural limitations of the airplane. Simulated emergency descents should be made in a turn to check for other air traffic below and to look around for a possible emergency landing area. A radio call announcing descent intentions may be appropriate to alert other aircraft in the area. When initiating the descent, a bank of approximately 30 to 45° should be established to maintain positive load factors (G forces) on the airplane. particular airplane. For the purposes of this handbook, inflight fires are classified as in-flight engine fires, electrical fires, and cabin fires.

 

[midlifeflyer]

Actually, here is the full section I quoted Airplane Flying Handbook Emergencies Page 17-6.

But wait. There's more. Turn the page.

Airplane Flying Handbook - Emergencies

 

[Clip4]

But wait. There's more. Turn the page.
Airplane Flying Handbook - Emergencies

That's why I prefer paper.

 

[luvflyin]

Lotsa stuff in this thread. Some guys even went out test flew different ways of doing it and got back to us with the numbers

https://www.pilotsofamerica.com/community/threads/emergency-descents.106588/#post-2388344

 

[RoscoeT]

If you solely want the fastest way down that is via a spin.

Spins may seem like an extreme way down, but it's not actually the fastest. In most you'll come down fastest banked steep at Vne, at max allowable G load.

 

[steingar]

Actually, there is not reason to pitch up and slow. Roll into the turn with proper elevator control and the airplane will slow into gear/flap speed quite quickly.

In your airplane maybe. An old saw among Mooney pilots. A Mooney will go down or slow down, but not at the same time.

 

[jsstevens]

Rolling into a step bank (say 60 degrees) and pulling will slow as fast as a zoom climb without gaining that much altitude. You directed the "up" vector of lift to the side. Read about IMC death spirals. It's that maneuver but done knowingly and under control. You're generating a large amount of induced drag to "climb" sideways while descending. More drag than with a slip (although you can combine all that together). Remember that if you just push over to Vne, you start with a nice descent rate but as your speed increases you'll have to shallow your descent to not exceed Vne AND you'll have to dissipate that speed energy before you land. And while I agree that all the concerns about being the airframe are minor if on fire, pulling the wings or tail off will not help you survive. They will, however, get you on the ground faster.

I'd love to see somebody actually try these methods and time each: 1) push to Vne and hold, then slow to landing speed and flare. 2) slow to flap speed (if needed), full flaps and slip then flare to land. 3) Bank 60 degrees pull then drop flaps and continue to pull to spiral down, level the wings and flare. 4) (nod to @EdFred here) spin down, recover, flare to land.

We can argue endlessly on these or we can get real data. (It's POA, I know, but we still can get real data.)

John

 

[sarangan]

I've got my PPL ride in a couple days and was doing some cruising online to make sure I haven't missed any small details and I ran into a few people discussing the ED procedure. Now I was taught by two different CFI's to use the no flaps, speed to top of green arc, 30-45 degree bank method. Others are suggesting slowing to Vfe, full flaps, then descend. I'm a bit conflicted here. I think if my examiner declares smoke in the cockpit or engine fire and I pitch up, it's probably not going to go well. Thoughts?

Flaps at top of green is likely to get you down faster. However, if the engine is on fire, then a higher airspeed might be useful to extinguish the flames. In some airplanes you can extend the first notch of flaps at a higher airspeed. So it all depends on what kind of emergency it is.

 

[EdFred]

Spins are prohibited in my plane or I would time all 4 descents from 10k to 3k.

 

[Tantalum]

Spins are prohibited in my plane or I would time all 4 descents from 10k to 3k.

All right, so which one of us has a 150 aerobat and is willing to try it?

 

[mscard88]

Flaps at top of green is likely to get you down faster. However, if the engine is on fire, then a higher airspeed might be useful to extinguish the flames. In some airplanes you can extend the first notch of flaps at a higher airspeed. So it all depends on what kind of emergency it is.

Believe you meant flaps at top of the white arc?

Here's how we teach 'em and the examiners here test it on check rides. Full flaps at top of white, roll 30-40* bank, keeps a positive G load.

The other method is top of the green. Runs the risk of exceeding Va, possibly structural damage, plus when you level off it takes awhile to slow.

Last but certainly not the least is what's in your POH. We have Cessnas and Pipers and neither brand has an ED profile for the models we have..

Again, this is what the DPE expect, so that's what we teach. Actually the full flap is fun.

And no, don't spin it down!

 

[ScottinIowa]

Believe you meant flaps at top of the white arc?

Here's how we teach 'em and the examiners here test it on check rides. Full flaps at top of white, roll 30-40* bank, keeps a positive G load.

The other method is top of the green. Runs the risk of exceeding Va, possibly structural damage, plus when you level off it takes awhile to slow.

Last but certainly not the least is what's in your POH. We have Cessnas and Pipers and neither brand has an ED profile for he models we have..

Again, this is what the DPE expect, so that's what we teach. Actually the full flap is fun.

And no, don't spin it down!

My DPE responded and this is pretty close to what he said. He said excessive airspeed doesn't equal fast descents. He said I need to be in a landing configuration to complete the task. Full flaps, no more than 30 degree bank, white arc, upwind, no obstructions. He said this way puts us in a quicker position to land, which of course is what we're trying to accomplish. Interesting how it is different than the two CFI's taught, but as many have said there's probably a few ways to skin this cat. I just think it's odd that as soon as you realize you're on fire, your first thought is to pitch up and slow down.

 

[tspear]

In your airplane maybe. An old saw among Mooney pilots. A Mooney will go down or slow down, but not at the same time.

'
Learn to use an overhead approach turn. Scrubs speed like crazy.
My guess in a Mooney with the slow flap and gear speed when compared to Vno and Vne this will still be slower then a steep bank to descent at Vne to steep bank down to slow down for landing.

Tim

 

[tspear]

My DPE responded and this is pretty close to what he said. He said excessive airspeed doesn't equal fast descents. He said I need to be in a landing configuration to complete the task. Full flaps, no more than 30 degree bank, white arc, upwind, no obstructions. He said this way puts us in a quicker position to land, which of course is what we're trying to accomplish. Interesting how it is different than the two CFI's taught, but as many have said there's probably a few ways to skin this cat. I just think it's odd that as soon as you realize you're on fire, your first thought is to pitch up and slow down.

I think your DPE is flat wrong. Engine fire, you want speed to try and blow out the fire if possible.
Even rolling to a 45 degree bank will scrub some speed, but the fastest way to potential energy is a knife edge turn which is beyond most of us; so a 60 degree bank will do the job just fine.

Tim