Slipping in turns for precision power off 180

[MBDiagMan]

Doc, have you ever gone to altitude and tried to stall your airplane while slipping like you would do in an approach to lose altitude? In most airplanes, you don't need to be any more concerned the your nose attitude (airspeed) during a slip than during a straight-in coordinated approach. Curious how your Cessna behaves. The planes I've tried this in (Champ, Cub, RV, Pitts) won't really even stall in a full slip, much less show any tendency to spin...the fear of which is the reason many folks get nervous during slips and tack on unnecessary airspeed, which defeats the purpose of the slip. YMMV in different airplanes. Not saying you're likely doing that, but many do. Now if you did a skidded approach, I'd pucker like most folks seem to do during slips...before they gain enough experience to realize how benign they generally are.

No, I've never experimented as you describe. That said, I've never felt that I was anywhere near a stall when I was slipping her. Quite honestly I've never paid particular attention to air speed when I slip, I think because I'm at a reasonable approach speed or I wouldn't be doing it.

Before the DPE yelled at me I never felt in any danger of any kind and when I was slipping for the DPE I THOUGHT that I was slipping exactly as I had done for the instructor numerous times with no complaint.

Another thing the DPE said about my 140 and he is a 140 owner himself, is that "you can slip a 140 all day long with full flaps." That seems to me to be even more indication that the plane is not easily stalled when slipping.

 

[poadeleted20]

I know the Com PTS wants a good wheels down landing

Yes, they do. You don't pass the test if you don't taxi back to the parking spot.

but real world a belly landing is another viable option if the prop stops IMO.

Agreed -- the resulting damage is the insurance company's problem, not yours, and I guarantee they're a lot happier with a trashed prop and damaged belly skin on the runway than a bunch of busted-up people in an off-airport location.

 

[Alexb2000]

No, I've never experimented as you describe. That said, I've never felt that I was anywhere near a stall when I was slipping her. Quite honestly I've never paid particular attention to air speed when I slip, I think because I'm at a reasonable approach speed or I wouldn't be doing it.

Before the DPE yelled at me I never felt in any danger of any kind and when I was slipping for the DPE I THOUGHT that I was slipping exactly as I had done for the instructor numerous times with no complaint.

Another thing the DPE said about my 140 and he is a 140 owner himself, is that "you can slip a 140 all day long with full flaps." That seems to me to be even more indication that the plane is not easily stalled when slipping.

That's one thing I love about Cessna's full flaps, full slip, no problem. In an emergency bring it in high, drop in with a full slip, you'll never come up short or long. So sad few pilots do this as SOP.

 

[Skylane81E]

Yes, they do. You don't pass the test if you don't taxi back to the parking spot.

Agreed -- the resulting damage is the insurance company's problem, not yours, and I guarantee they're a lot happier with a trashed prop and damaged belly skin on the runway than a bunch of busted-up people in an off-airport location.

I only know of one person to pass a check ride and crash the plane on the same flight. CFI I flew with a few times bellyed in a beech 18 on his multi com ride. When the gear didn't come down he asked the examiner if he wanted to make the landing. The response "you have more multi time than me!" sealed the deal and Bob put it down next to the runway.

Leave it to a B-17 pilot

 

[Skylane81E]

That's one thing I love about Cessna's full flaps, full slip, no problem. In an emergency bring it in high, drop in with a full slip, you'll never come up short or long. So sad few pilots do this as SOP.

Yep, besides in MOST cases I'd rather go off the end slow than come up short at flying speed.

 

[CBeaulieu]

That's one thing I love about Cessna's full flaps, full slip, no problem. In an emergency bring it in high, drop in with a full slip, you'll never come up short or long. So sad few pilots do this as SOP.

Some people don't realize you can slip a 172 because of a placard on the panel that says "Slips not advised" (perhaps only in Cessnas with 40* of flaps?). With full flaps and in a slip, you feel a buffet which some may mistake for a stall. The buffet is real rythmic and is easily ruled out as being associated with a stall though.

 

[somorris]

I used to slip our 172, but it did say they weren't recommended in the Owner's Manual. I think the deal was with full flaps the elevator could get shielded and cause the nose to bob up and down.

 

[jason]

I used to slip our 172, but it did say they weren't recommended in the Owner's Manual. I think the deal was with full flaps the elevator could get shielded and cause the nose to bob up and down.

It's fine. Really...slip away.

 

[somorris]

Hi Jason. I can't slip our 172 anymore -- we sold it a few years ago. We have a C-150 now. I slip it frequently. .

 

[Seanaldinho]

turning slips are required maneuvers for an glider rating

For my checkride I had to fly a pattern without spoilers until Final. To add to the challenge he disco'ed us at 700 feet. So immediately I turn downwind and once appropriate kick in a slip, turn to base in the slip, and turn final in a slip then he unlocked the spoilers for me even though I didnt need them so I flew it down to fifty feet in a slip then open the spoilers to prevent ballooning.

 

[gismo]

Use a lot of rudder and just enough opposite aileron to keep the wings level.

That sounds like a skid to me.

 

[gismo]

Adding excess speed in a slip to lose altitude doesn't gain you anything. When you come out of the slip back to a normal glide you will have all that excess speed(energy) to lose. While you are dissipating the energy your are floating down the runway.

That's not entirely true. If the goal of your slip is to dissipate excess energy, the fast you're going when you slip, the faster you shed energy. The trick is to lose the excess speed by the time you terminate the slip, and that may require a bit of practice.

 

[dillardrg]

Putting the nose down when flying sideways converts altitude into drag like it's going out of style. .

Oh, you will descend like it is going out of style, but at the same time you are building excess energy that must be dissipated. You will get much better results by not lowering the nose.

A little bit of slip will get rid of the energy in short order.

If you do not lower your nose in the initial slip, you will not have to do another slip to dissipate the energy.

I still encourage actually trying slips at various attitudes to see how your airplane performs. Unless you do this, you don't know.

 

[gismo]

Very important, keep nose down, very important.

Of course what the other folks say about slips-n-stalls is true but if the nose is down then the AOA < critical AOA and there won't be a problem. Just watch it at the round-out.

In every airplane I've slipped (i.e. quite a few), if you simply maintained the same pitch attitude when slipping as you had prior to the slip, the airspeed would remain constant. It is true that slipping at the same pitch attitude generates a higher AoA than coordinated flight because the increased descent rate lowers the angle of the relative wind so you are getting slightly closer to a stall but if you were at 1.3 Vso to start with you'll still be a long way from stalling.

So like you said, if you don't let the nose come up (increased pitch attitude) things will be fine. Doesn't mean you need to drop the nose though unless you were really close to stalling in the first place.

 

[dillardrg]

That's not entirely true. If the goal of your slip is to dissipate excess energy, the fast you're going when you slip, the faster you shed energy. The trick is to lose the excess speed by the time you terminate the slip, and that may require a bit of practice.

Normally when I slip it is to lose excess altitude, not dissipate excess energy.

My goal, then is to lose excess altitude without gaining excess energy that needs to be dissipated when you come out of the slip.

Again, try slips at various ATTITUDES to see which attitude allows you to lose the altitude with gaining the excess energy. You will not know this unless you try it.

 

[gismo]

Oh, you will descend like it is going out of style, but at the same time you are building excess energy that must be dissipated. You will get much better results by not lowering the nose.

If you do not lower your nose in the initial slip, you will not have to do another slip to dissipate the energy.

I still encourage actually trying slips at various attitudes to see how your airplane performs. Unless you do this, you don't know.

While you're trying that, do a little experiment with fast vs slow slips. If you start at at least a few thousand AGL and 1.3 Vso and descend for a fixed distance on you GPS I think you'll find that you'll lose more altitude if you increase the speed to Va during the descent vs holding 1.3 Vso all the way, even accounting for the distance covered while slowing back to the original speed in level flight. This is even more true if you hold the slip while slowing.

Normally when I slip it is to lose excess altitude, not dissipate excess energy.

Excess altitude is excess energy. Just in kinetic form.

 

[dillardrg]

In every airplane I've slipped (i.e. quite a few), if you simply maintained the same pitch attitude when slipping as you had prior to the slip, the airspeed would remain constant. It is true that slipping at the same pitch attitude generates a higher AoA than coordinated flight because the increased descent rate lowers the angle of the relative wind so you are getting slightly closer to a stall but if you were at 1.3 Vso to start with you'll still be a long way from stalling.

So like you said, if you don't let the nose come up (increased pitch attitude) things will be fine. Doesn't mean you need to drop the nose though unless you were really close to stalling in the first place.

In my Citabria if I keep my normal 70mph glide ATTITUDE when entering a slip, even though my airspeed INDICATION remains fairly constant when I come out of the slip my airspeed is 85mph. I must then lose that extra 15mph.

If when I enter a slip I put the airplane in a climb attitude and when I come out of the slip put it back in the normal glide attitude it is right on the 70mph I had when entering the slip. This is my airplane, YMMV.

I hate to sound like a broken record, but if you don't try slips in various attitudes you have no idea which is the best attitude for both losing altitude and not gaining excess energy IN YOUR AIRPLANE.

 

[gismo]

Again, try slips at various ATTITUDES to see which attitude allows you to lose the altitude with gaining the excess energy. You will not know this unless you try it.

Actually I have tried it and I know from whence I speak (er, write). It's also quite easy to show mathematically why a higher speed slip will lose altitude more effectively even if you include the time spend slowing down.

 

[dillardrg]

While you're trying that, do a little experiment with fast vs slow slips. If you start at at least a few thousand AGL and 1.3 Vso and descend for a fixed distance on you GPS I think you'll find that you'll lose more altitude if you increase the speed to Va during the descent vs holding 1.3 Vso all the way, even accounting for the distance covered while slowing back to the original speed in level flight. This is even more true if you hold the slip while slowing.

Excess altitude is excess energy. Just in kinetic form.

I agree with that, I am talking about losing altitude in the pattern. By maintaining a constant attitude in the slip I am able to predict what is happening through out(staying stabilized, as it were). If I need to lower then raise the nose things are a lot less predictable.

All my posts refer to what happens with MY AIRPLANE. Theory is fine until you meet up with reality. Everyone flying a different airplane will have different results. That is why I urge you to try slipping using various attitudes to find out which results in the best performance for your airplane.

Trying this at altitude will also result in more pilots actually finding out that slipping is fun, not dangerous.

 

[Skylane81E]

Normally when I slip it is to lose excess altitude, not dissipate excess energy.

My goal, then is to lose excess altitude without gaining excess energy that needs to be dissipated when you come out of the slip.

Again, try slips at various ATTITUDES to see which attitude allows you to lose the altitude with gaining the excess energy. You will not know this unless you try it.

Altitude is energy

 

[poadeleted20]

I only know of one person to pass a check ride and crash the plane on the same flight.

Must have been a very long time ago. Any sort of accident is a mandatory disapproval, and has been for many years.

 

[Skylane81E]

Shortly after the end of the war. No later than 46 I'd imagine.

 

[Capt. Geoffrey Thorpe]

Oh, you will descend like it is going out of style, but at the same time you are building excess energy that must be dissipated. You will get much better results by not lowering the nose.

I have to assume that you have not actually tried this.

The little bit of excess speed can be lost in about the last 3 or 4 seconds of slipping - that's the thing about flying sideways with the pedal to the floor, the airplane doesn't accelerate well and it decelerates quickly.

The extra altitude / energy lost is lost.

 

[spinfire]

My excellent transition training instructor for the Cardinal demonstrated a stall from a slip. He asked me if I had ever experienced a cross controlled stall and I said I hadn't. Many pilots are afraid of it because of misconceptions. We got it pretty deeply stalled. The nose just bobs there as you descend. You can easily hold it just on the edge of the stall. Of course, this airplane has pretty nice stall characteristics, but in general a cross controlled stall is just another maneuver and not to be feared.

Aren't CFI candidates required to demonstrate cross controlled stalls? Where does this notion that you are going to flip the plane by stalling it in a slip come from? Certainly not from CFIs who passed their CFI ride? Sigh.

 

[gismo]

Must have been a very long time ago. Any sort of accident is a mandatory disapproval, and has been for many years.

Would a "crash" due to a gear malfunction result in a pink slip provided that the pilot had accomplished all necessary tasks prior to the crash?

 

[CBeaulieu]

Aren't CFI candidates required to demonstrate cross controlled stalls? Where does this notion that you are going to flip the plane by stalling it in a slip come from? Certainly not from CFIs who passed their CFI ride? Sigh.

Everyone is taught to keep the ball centered when performing a stall during primary training. It probably has something to do with this.

 

[Capt. Geoffrey Thorpe]

A Pitts pilot thinks a power off slipping 180 is dangerous? He needs his Pitts card revoked! I took some video of how I do it in mine every time. Haven't died yet:

http://vimeo.com/34737384

You exceeded 30 degrees in the pattern. I'm sure that you did die. Probably more than once.

 

[poadeleted20]

Would a "crash" due to a gear malfunction result in a pink slip provided that the pilot had accomplished all necessary tasks prior to the crash?

If the practical test was completed before the accident, then the accident would not have occurred during the practical test. Note, however, the "Postflight Procedures" tasks such as on the PP-A PTS:

Task A: After Landing, Parking, and Securing (AMEL and
AMES)
​

​

References: FAA-H-8083-3, FAA-H-8083-23; POH/AFM.​

Objective:

To determine that the applicant:

1. Exhibits satisfactory knowledge of the elements related to
after landing, parking, and securing procedures.
2. Maintains directional control after touchdown while
decelerating to an appropriate speed.
3. Observes runway hold lines and other surface control
markings and lighting.
4. Parks in an appropriate area, considering the safety of
nearby persons and property.
5. Follows the appropriate procedure for engine shutdown.
6. Completes the appropriate checklist.
7. Conducts an appropriate postflight inspection and secures​

the aircraft.
​

Hard to complete those after a crash. That said, in the case you posit of landing gear which refused to extend, I'm pretty sure the practical test would be discontinued before the belly landing occurred, in which case the "accident" would not have occurred during the practical test.
​

 

[jjflys]

On my PPL check ride (in a 172N) after I demonstrated short, soft, a forward slip and a go around the DPE said "my plane" and proceeded to demonstrate a power off 180. There was slipping involved in all the turns and I have to say it was pretty cool.

 

[Bobcat1]

A Pitts pilot thinks a power off slipping 180 is dangerous? He needs his Pitts card revoked! I took some video of how I do it in mine every time. Haven't died yet:

http://vimeo.com/34737384

+1. That's how it's been done for years. We've got CFIs who are afraid to lower the wing in a slip now?

 

[Fearless Tower]

Shortly after the end of the war. No later than 46 I'd imagine.

Why was he taking a check ride??

My grandfather left the AAF with a Commercial ASEL/AMEL based off his military training and flight time. I don't think he had to take a check ride and I know he never set foot in a civil multi-engine bird as a pilot (I have his logbook).


Sent from my iPad using Tapatalk HD

 

[poadeleted20]

Why was he taking a check ride??

Two possibilities, based on the FAA rules up to a few years ago, which may or may not have been the same as the rules in 1946. First, you only got the ratings for aircraft in which you were qualified in the military. If he was a single-engine fighter pilot or training command instructor, he would not have qualified in ME airplanes in the military, and would need a CAA checkride in an ME airplane to add that to his ticket. Second, it might have been more than 12 months since his last flight in a twin in the military, and up until a few years ago, the FAA only gave tickets to military pilots based on what they had flown within the preceding 12 months -- wait 13 months after you left the military, and you got nothing based on military competency and had to take the practical test for that certificate/rating.

My grandfather left the AAF with a Commercial ASEL/AMEL based off his military training and flight time. I don't think he had to take a check ride and I know he never set foot in a civil multi-engine bird as a pilot (I have his logbook).

If he applied for his civilian license within 12 months of flying both SE and ME in the military, he would get both ratings.

Note that the current rules are very different, and allow you to obtain an FAA ticket with ratings in whatever you were qualified in the military no matter how long ago. So, if someone who flew Stearmans in training and B-17's operationally during WWII but hadn't flown anything since walked into the FSDO today with the documentation (and, of course, an appointment), he would get a CP-ASMEL-IA with a B-17 type rating, and be grandfathered for complex, high performance, tailwheel, and high-altitude aircraft.

 

[gismo]

If the practical test was completed before the accident, then the accident would not have occurred during the practical test. Note, however, the "Postflight Procedures" tasks such as on the PP-A PTS:
Hard to complete those after a crash. That said, in the case you posit of landing gear which refused to extend, I'm pretty sure the practical test would be discontinued before the belly landing occurred, in which case the "accident" would not have occurred during the practical test.

Task A: After Landing, Parking, and Securing (AMEL and

AMES)
​

References: FAA-H-8083-3, FAA-H-8083-23; POH/AFM.​

Objective:
To determine that the applicant:

1. Exhibits satisfactory knowledge of the elements related to
after landing, parking, and securing procedures.
2. Maintains directional control after touchdown while
decelerating to an appropriate speed.
3. Observes runway hold lines and other surface control
markings and lighting.
4. Parks in an appropriate area, considering the safety of
nearby persons and property.
5. Follows the appropriate procedure for engine shutdown.
6. Completes the appropriate checklist.
7. Conducts an appropriate postflight inspection and secures​

the aircraft.

Seems like #1 could be accomplished verbally and the decel part of #2 sounds likely. Prolly no issues with #3,5,6,7 but #4 might be a problem.