Power Off 180, CFI Says X, I Say Y

[Therookguy]

Everything you teach a commercial student applies to every aircraft that they may fly, through their entire career?

I teach power off 180s utilizing slips quite often and some times with no flaps during the entire procedure to demonstrate the maneuver can be accomplished to commercial ACS standards without the use of any flaps.
When the pilot uses proper ADM prior to the point of power reduction to touch down, there is zero reason for and uncoordinated base to final turn. And let’s be clear, that accurately describes what forward slip in this turn is - nothing more than an uncoordinated turn.

If the pilot needs an uncoordinated base to final turn, it’s likely a result of 4 misjudgments (wind direction / velocity, distance laterally from the runway on the downwind, distance to turn from downwind to base and altitude immediately after they completed the turn to base) and insufficient knowledge of proper energy management concepts.

I do not teach an uncoordinated base to final turn because I am concerned it encourages a poor practice that can get any pilot in deep doo doo rather quickly. A CFI has to recognize the procedures they are teaching to rather low time commercial trainees are applicable to all make/model/gross weight/CG of every aircraft that trainee may latter fly. I am not going to teach using top or bottom rudder in the base to final turn because you mess it up, the results are catastrophic.

I don't agree with Clip4 here, Slips, particularly slips to landing, need to at least be taught as a tool and learned. I don't mind and can totally see teaching "hey this is a little dangerous and maybe uncomfortable for you or your passengers so don't use it unless you have to." It's literally a maneuver in the commercial ACS. You never know what flying a student is going to go on to do and there are plenty of times in GA or elsewhere where you have to use a forward slip to land safely. For example, there are several "no go around" airports in the US where you have to land properly on the first attempt. Also what if you don't have an engine and have to hit your spot?

They're a maneuver in ACS's and in the Airplane Flying Handbook. I would rather my student be confident in their knowledge of aerodynamics, stalling, loading, and angle of attack such that they could confidently employ top rudder when they need to rather than just being afraid of it.

 

[Therookguy]

I would also also like to add one last comment about forward slips. They are very important for engine management. They're a very useful tool for preventing shock cooling of your engine. You can maintain a decent rate of decent while keeping power in. If I ever get "Slam dunked" by ATC on an approach I'll use this to protect my 6 cylinder Lycoming. Sure it scares my wife a little but it's better than 40-50k for a new engine.

Also having some power in during slips makes it easier to pull out of them and were you to get towards a stalling condition (again, not likely with the low AoA) it's a faster recovery.

Point being don't be afraid to play around with slips. Don't play with skids though.

 

[decalogue]

I would also also like to add one last comment about forward slips. They are very important for engine management. They're a very useful tool for preventing shock cooling of your engine. You can maintain a decent rate of decent while keeping power in. If I ever get "Slam dunked" by ATC on an approach I'll use this to protect my 6 cylinder Lycoming. Sure it scares my wife a little but it's better than 40-50k for a new engine.

Also having some power in during slips makes it easier to pull out of them and were you to get towards a stalling condition (again, not likely with the low AoA) it's a faster recovery.

Point being don't be afraid to play around with slips. Don't play with skids though.

Play with both with a good instructor or mentor pilot and at a safe altitude in a plane that can spin and is as similar to what you commonly fly as possible. Learn what does what and what leads to what.

 

[MauleSkinner]

Sure it scares my wife a little but it's better than 40-50k for a new engine.

I’d suggest a different technique if it scares your wife.

 

[decalogue]

I’d suggest a different technique if it scares your wife.

New wife?

 

[MauleSkinner]

New wife?

That may be his goal.

 

[MauleSkinner]

Some upstream mentioned slow flight to increase drag and sink rate. The problem is that you can also run out of elevator control authority for the flair, as per the recent Beech forced landing on a runway through the power lines.

Note that slowing to increase drag and then lowering the nose to increase energy for the flare is very different from pulling the nose up to try and stretch a glide and taking that slow speed all the way to the ground.

Much like a full cross-controlled slip is taken out, at least partially, prior to touchdown.

 

[bentmettle]

Hey Y’all
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My larger concern is what happens when those same students are endorsed for solo. If we normalize slipping in a turn at low altitude as an acceptable correction, we have to assume they might attempt that maneuver alone, without an instructor in the right seat. A developing student pilot who is still re

I realize that this is the way of the internet, but you began the discussion talking about a commercial maneuver. Then you’ve gone on some tangent about low time pilots.

Pick an expectation. They aren’t the same for commercial.

 

[bentmettle]

I was summoned and posted in haste. I appreciate this discussion and it shows me I need to revisit my ability to explain slips to people.

the best part of practicing the 180 is that transition out of the forward slip into the last little bit of round out quickly going into the flare.

 

[decalogue]

I would also also like to add one last comment about forward slips. They are very important for engine management. They're a very useful tool for preventing shock cooling of your engine. You can maintain a decent rate of decent while keeping power in. If I ever get "Slam dunked" by ATC on an approach I'll use this to protect my 6 cylinder Lycoming. Sure it scares my wife a little but it's better than 40-50k for a new engine.

Also having some power in during slips makes it easier to pull out of them and were you to get towards a stalling condition (again, not likely with the low AoA) it's a faster recovery.

Point being don't be afraid to play around with slips. Don't play with skids though.

I missed the first part, per shock cooling you just have to manage power, mixture, cowl flaps, gear & secondary controls, even glider tow pilots & skydive pilots do not slip on the way down.

 

[Lindberg]

[E]ven glider tow pilots . . . do not slip on the way down.

Maybe some don't.

 

[Rick A]

Guess I'm a little negligent. I don't find any need to skid, ever. My ball stays centered unless I'm slipping. Maybe if I was a crop duster with lots of power and experience.

But slips, absolutely love them. They have a purpose that puts them on the "use when needed" list of stick and rudder skills.

 

[RoscoeT]

He argues that using right rudder in a left turn to induce a skid can be accomplished safely with proper control and awareness.

Right rudder in a left turn produces a slipping turn, not a skid. Slips are quite spin resistant. I'm not a CFI and can't speak to how soon slipping turns should be introduced to student pilots, but no licensed pilot should be unable to comfortably and safety do a slipping turn if desired.

 

[Rick A]

I would also also like to add one last comment about forward slips. They are very important for engine management. They're a very useful tool for preventing shock cooling of your engine. You can maintain a decent rate of decent while keeping power in. If I ever get "Slam dunked" by ATC on an approach I'll use this to protect my 6 cylinder Lycoming. Sure it scares my wife a little but it's better than 40-50k for a new engine.

Also having some power in during slips makes it easier to pull out of them and were you to get towards a stalling condition (again, not likely with the low AoA) it's a faster recovery.

Point being don't be afraid to play around with slips. Don't play with skids though.

You should become aware that a "slam dunk" is coming as your distance to the airport is closing and ATC is obviously setting you up for the dunk. If you haven't asked for lower beforehand, and been refused lower, that's the time to throttle back while level, slow down (cool down), and when ATC gives you the dunk lower the gear, reduce the throttle more, and establish a healthy descent rate.

Needing to slip in the above scenario to "save your hot 6 cylinders" indicates a lack of situational awareness and not being ahead of the plane.

 

[Clip4]

Everything you teach a commercial student applies to every aircraft that they may fly, through their entire career?

Sure, one isn’t likely to be performing steep spirals and power off 180s in a business jet, but I you read the Miracle on the Hudson story you will see when properly taught basics effect the outcome.

 

[Clip4]

Right rudder in a left turn produces a slipping turn, not a skid. Slips are quite spin resistant. I'm not a CFI and can't speak to how soon slipping turns should be introduced to student pilots, but no licensed pilot should be unable to comfortably and safety do a slipping turn if desired.

While a slipping base-to-final turn is not an automatic failure on a commercial checkride, it demonstrates a failure to plan the approach, indicates poor energy management potentially violating stability or precision standards.

 

[MauleSkinner]

While a slipping base-to-final turn is not an automatic failure on a commercial checkride, it demonstrates a failure to plan the approach, indicates poor energy management potentially violating stability or precision standards.

So what do you recommend as an alternative on the power off 180 if the approach was improperly planned?

 

[Mikey52]

Haven't had a chance to post here, i must be slipping.

 

[decalogue]

While a slipping base-to-final turn is not an automatic failure on a commercial checkride, it demonstrates a failure to plan the approach, indicates poor energy management potentially violating stability or precision standards.

For a power off 180, I should hope not, it is not a stabilized approach maneuver

If you hit the point -0/+200, no crazy excessive side load or slam on landing, it’s a pass.

 

[MauleSkinner]

Haven't had a chance to post here, i must be slipping.

You did post on the previous page…you must be slipping.

 

[dtuuri]

You did post on the previous page…you must be slipping.

Might be sipping, just sayin'...

 

[flyingcheesehead]

That is not exactly true - at least not the extent that you seem to think it is. Load factor and stall speed noticeably increase in a turn when you are trying to maintain altitude because of the reduced vertical component of lift.

The ole 60 degree turn equals 2gs is for a LEVEL 60 degree steep turn.

But in the power off 180, you are in a descending turn - working with an unloaded wing so to speak.

Being in a constant rate descent DOES NOT unload the wing. Any vertically unaccelerated flight has the same load factor for the same conditions, ie, a 60-degree steep turn is going to be 2G whether you do it level, in a 500 fpm climb, or in a 1000 fpm descent.

When you unload the wing, you are reducing lift and *accelerating* downwards. At some point that acceleration has to stop, and you'll need a load factor >1 to arrest the descent.

I hope you are teaching slips to proficiency prior to solo. How will the solo student land in a crosswind?

There's a difference between a slightly cross controlled slip to counteract the crosswind component on landing, a straight ahead forward slip to landing to increase descent rate if necessary, and a turning slip which is the most difficult to safely do of the three.

Turning slips are not a required maneuver at any level, and they are the most difficult of the three, and I think it's quite prudent of our soon-to-be-newbie-CFI OP to stick to the safer, required versions of the maneuver.

 

[MauleSkinner]

Turning slips are not a required maneuver at any level,

Agreed.

and they are the most difficult of the three, and I think it's quite prudent of our soon-to-be-newbie-CFI OP to stick to the safer, required versions of the maneuver.

I tend to disagree, with both the “most difficult” as well as any suggestion that could be construed as only teaching to the test.

 

[flyingcheesehead]

I tend to disagree, with both the “most difficult” as well as any suggestion that could be construed as only teaching to the test.

I don't think they're excessively difficult, but there are certainly a couple of extra things one needs to think about when doing them.

I'm not a fan of teaching to the test, but I'm also not a fan of the "one must be a god of flying and successfully complete inverted flat spins to a grass strip landing in night IMC before being signed off to solo" philosophy that some folks appear to have on the Internet.

I think the OP's cautious approach to teaching extra things to new students *as a new CFI* is a smart approach. Once he's sure he's effective at getting all the right ideas across, sure, do more.

 

[Dan Thomas]

I missed the first part, per shock cooling you just have to manage power, mixture, cowl flaps, gear & secondary controls, even glider tow pilots & skydive pilots do not slip on the way down.

When I was a glider tow pilot in the 1970s I did a lot of slipping, really aggressive slips to get back down to the airport for the next tow. If I had just glided down those guys would not be happy with waiting so long.

Slips are safe. Skids are not.

 

[MauleSkinner]

When I was a glider tow pilot in the 1970s I did a lot of slipping, really aggressive slips to get back down to the airport for the next tow. If I had just glided down thoes guys would not be happy with waiting so long.

Slips are safe. Skids are not.

Likewise (although in the 1980s.) PA-12, 70+ degrees of bank, full top rudder, airspeed indicating below the numbered range, and enough back stick for a tight spiral.

WHEEEEEE!

 

[MauleSkinner]

I think the OP's cautious approach to teaching extra things to new students *as a new CFI* is a smart approach. Once he's sure he's effective at getting all the right ideas across, sure, do more.

On the other hand, more exposure to slips in various forms would make new students more comfortable with the ACS-required versions, and I get the impression that the OP himself isn’t really comfortable with slips. Most pilots get just enough training in slips to pass the test, and as Tony indicated, just enough often isn’t. Having had a couple of pilots initiate snap rolls on final when I suggested a slip, I would tend to think that slips are significantly under-trained.

 

[Clip4]

For a power off 180, I should hope not, it is not a stabilized approach maneuver

If you hit the point -0/+200, no crazy excessive side load or slam on landing, it’

Knowledge: The Applicant demonstrates understanding of:
CA.IV.M.K1. A stabilized approach including energy management concepts.

If it isn’t a stabilized approach, why is the applicant required to demonstrate knowledge of a stabilized approach?

 

[MauleSkinner]

That’s not what the ACS says.

Knowledge: The Applicant demonstrates understanding of:
CA.IV.M.K1. A stabilized approach including energy management concepts.

Slips are an energy management concept.

 

[Clip4]

On the other hand, more exposure to slips in various forms would make new students more comfortable with the ACS-required versions, and I get the impression that the OP himself isn’t really comfortable with slips. Most pilots get just enough training in slips to pass the test, and as Tony indicated, just enough often isn’t. Having had a couple of pilots initiate snap rolls on final when I suggested a slip, I would tend to think that slips are significantly under-trained.

I think some here omit risk management, which is included in the Objective of the task. An airplane can enter a spin from a slipping turn, although it is less common than from a skidding turn. A slipping turn increases stall speed and risk, so it is safer to coordinate the turn, align the aircraft early, and use forward slips on final or straight-and-level on base to lose excess altitude.

In my view, an intentional uncoordinated base to final turn is an unstable approach in this maneuver and a DPE should consider a flunk of every applicant that performs the task in that fashion because on a commercial ride they are supposed to be demonstrating mastery of the aircraft and not taking unnecessary risks.

 

[decalogue]

Knowledge: The Applicant demonstrates understanding of:
CA.IV.M.K1. A stabilized approach including energy management concepts.

If it isn’t a stabilized approach, why is the applicant required to demonstrate knowledge of a stabilized approach?

Yeah slips are a accepted energy mangement concept for a power off 180

FAA AFM chapter 9 states slips and S turns

The CPL ACS also mentions slips in risk mgmt when needed

Also people who actually fly airplanes professionally don’t frown on slips when needed

 

[RyanShort1]

I think some here omit risk management, which is included in the Objective of the task. An airplane can enter a spin from a slipping turn, although it is less common than from a skidding turn. A slipping turn increases stall speed and risk, so it is safer to coordinate the turn, align the aircraft early, and use forward slips on final or straight-and-level on base to lose excess altitude.

In my view, an intentional uncoordinated base to final turn is an unstable approach in this maneuver and a DPE should consider a flunk of every applicant that performs the task in that fashion because on a commercial ride they are supposed to be demonstrating mastery of the aircraft and not taking unnecessary risks.

Clip, when was the last time you flew a plane that didn’t have flaps?

 

[ColinD]

The 'Knowledge' portion of Task M (power-off 180) requires the applicant demonstrate understanding of a stabilized approach, but there is no mention of maintaining a stabilized approach in the 'Skills' portion of that task:

Skills: The applicant exhibits the skill to:

CA.IV.M.S1 Complete the appropriate checklist(s).

CA.IV.M.S2 Make radio calls as appropriate.

CA.IV.M.S3 Plan and follow a flightpath to the selected landing area considering altitude, wind, terrain, andobstructions.

CA.IV.M.S4 Select the most suitable touchdown point based on wind, landing surface, obstructions, and aircraftlimitations.

CA.IV.M.S5 Position airplane on downwind leg, parallel to landing runway.

CA.IV.M.S6 Correctly configure the airplane.

CA.IV.M.S7 As necessary, correlate crosswind with direction of forward slip and transition to side slip beforetouchdown.

CA.IV.M.S8 Touch down at a proper pitch attitude, within 200 feet beyond or on the specified point with no side driftand with the airplane’s longitudinal axis aligned with and over the runway centerline or landing path, as applicable.

Compare and contrast with something like Task D (soft-field landing,) where the 'Skills' portion requires the applicant establish and maintain a stabilized approach:

CA.IV.D.S6 Establish the recommended approach and landing configuration, airspeed, and trim, and adjust pitch attitude and power as required to maintain a stabilized approach.

"This won't be a textbook stabilized approach, but I'm going to do what's necessary to hit my point." Understanding demonstrated, no?

 

[bentmettle]

Isn’t the defacto requirement of many of the performance maneuvers to trim the margin of risk down to achieve maximum performance?

The test was always going to force risky behavior when you require landing on a specific spot with no go around. The design of the exam requires you trim the margins.

The FAA might as well have scored checkride for the purposes of giving the airlines some discriminator because failing one day and retaking the next only serves to add a note in your record, not improve your airmanship in any real way.

 

[MauleSkinner]

I think some here omit risk management, which is included in the Objective of the task. An airplane can enter a spin from a slipping turn, although it is less common than from a skidding turn. A slipping turn increases stall speed and risk, so it is safer to coordinate the turn, align the aircraft early, and use forward slips on final or straight-and-level on base to lose excess altitude.

In my view, an intentional uncoordinated base to final turn is an unstable approach in this maneuver and a DPE should consider a flunk of every applicant that performs the task in that fashion because on a commercial ride they are supposed to be demonstrating mastery of the aircraft and not taking unnecessary risks.

One aspect of risk management is the understanding of and proficiency in the elements of the risk being managed. I see a lot of pilots refuse to do things under the banner of risk management simply because they don’t know or understand what’s involved, and refuse to take the time and effort to learn.

 

[Fearless Tower]

Being in a constant rate descent DOES NOT unload the wing. Any vertically unaccelerated flight has the same load factor for the same conditions, ie, a 60-degree steep turn is going to be 2G whether you do it level, in a 500 fpm climb, or in a 1000 fpm descent.

When you unload the wing, you are reducing lift and *accelerating* downwards. At some point that acceleration has to stop, and you'll need a load factor >1 to arrest the descent.

The G meter in my T6 would disagree.

Doing a power off 180 in the T6, when I roll into a a heavy bank, the needle in the G meter is not climbing like it would in a level turn. And I'm not having to put any real back pressure on the stick either as long as I set me trim properly before I start the turn.

When I land the Stearman, virtually every landing is a power off 180. When the power goes to idle abeam the intended landing point, the trim immediately goes to the 10 o'clock position and stays there until I land. I need apply very little back pressure on the stick until the flare.

To clarify, when I say 'unload the wing' I mean reducing the load compared to what it would be in a level turn - not implying no load.

Consider this: if you are flying straight and level you are at 1g. If you push the stick left and roll into a 60 degree bank and don't push forward or pull back what's the airplane going to do?

It is going to start turning left due to the horizontal component of lift.

It is also going to start to descend due to the vertical component of lift.

The G load will not automatically increase UNLESS you pull back on the stick to reduce the descent rate, but in the OP's example, you wouldn't do that because you are too high on the approach and therefore need to increase your descent rate.

 

[dtuuri]

Consider this: if you are flying straight and level you are at 1g. If you push the stick left and roll into a 60 degree bank and don't push forward or pull back what's the airplane going to do?

Consider that even while wings level there is an angle of attack trying to curve the plane upward. When you tilt, gravity loses part of its effectiveness to prevent the curving flight. The resulting curve causes an increase in g load above 1 g.

 

[mryan75]

So your solution is a time machine? You can only get to the runway from where you are, not where you were.

But he can get to the runway, he might just overshoot the 200 feet. To me that’s doing it right. “It’s always better to go off the end of a runway slowing down than to come up short of it.”

 

[MauleSkinner]

But he can get to the runway, he might just overshoot the 200 feet. To me that’s doing it right. “It’s always better to go off the end of a runway slowing down than to come up short of it.”

I’d rather see someone use the tools available to make the target.

 

[dmspilot]

Consider this: if you are flying straight and level you are at 1g. If you push the stick left and roll into a 60 degree bank and don't push forward or pull back what's the airplane going to do?

It will enter a steep spiral.

I've done the math here before but I'll do it again. Gravity is ~32ft/s2, in a 60°-banked turn at a load factor of 1, the vertical component of lift is reduced 50%, resulting in a downward acceleration of 16ft/s2 or 960fpm/s. This will peg a 2000fpm VSI in 2.08 seconds. In a 45° banked turn, it takes about four seconds. Yes I've tested it in real life. The empirical data matches the math.

The G load will not automatically increase

Yes it will, as the airspeed will increase and the airplane's longitudinal stability will cause the AoA to increase.