To full flaps or not to full flaps!

[Beefitarian]

"There's your problem, full flap reduces the rudder's effectiveness on that plane."

When you add full flaps some of the airflow that goes to the tail is deflected (high wing), hence the effectiveness reduction in the rudder. Try doing a forward-slip without flaps and full flaps and you will notice some difference. Now when it comes to landing it will only affect if you have to use full rudder.

I did and that is pretty much how I remember it.

[fish4life]

keep in mind once the aircraft start to get a bit larger if you don't use full flap you run a greater risk of tail strikes... Hell we have a older 150 with the swept tail (no rear window) and if you flare too much without flaps you'll tail strike

[Beefitarian]

I've never done it but I noticed during the walk around someone's dragging the eyebolt or whatever's on the back of lots of 172s I've flown.

[burhead1]

I've never done it but I noticed during the walk around someone's dragging the eyebolt or whatever's on the back of lots of 172s I've flown.

Shhh it was Me

[Beefitarian]

It's ok bur, that's why they use an eyebolt or that little aluminum angle bracket to protect the tail.

[Big Pistons Forever]

I hate "one size fits all pronouncements" of the right way to do something, like "always land with full flap". The amount of flap I use is appropriate to the aircraft and the conditions. Little airplanes with big flaps, like the single Cessna's all seem to do better with less flap in strong crosswinds. Little airplanes with small flaps like Grummans do better with full flaps under all conditions. Heavier aircraft like the Pa31, work fine with full flaps, although 400 series Cessna's can be a bit easier to handle with less than full flaps, if you have a long runway. Transport catagory aircraft are landed with the flap specified in the AFM for the runway length.

[skybaron]

I've never used full flap with the beav.

You have never used full flaps on a Beaver?

Do you fly one for a living?

Try using full flap in high winds with a STOL wing and you will think harder the next time you pump them all the way down.

Using full flaps in a Beaver in high winds would be poor judgment making for sure, but the airplane was designed and approved for the flap range available, therefore it is safe to use full flap if needed.

From the DHC-2 AFM:

"Full Flap is only required for emergency landing in very restricted areas".

Then:

Minimum run landings may be necessary under EXDRAORDINARY circumstances.

"pilots familiar with the aircraft and experienced in short landing technique may perform minimum run landings by using full flap & reducing airspeed on the final approach to 65-68mph & maintaining that speed to the point of flare out"

+1 on one size doesn't fit all.

[Cat Driver]

From the DHC-2 AFM:

"Full Flap is only required for emergency landing in very restricted areas".

Then:

Minimum run landings may be necessary under EXDRAORDINARY circumstances.

"pilots familiar with the aircraft and experienced in short landing technique may perform minimum run landings by using full flap & reducing airspeed on the final approach to 65-68mph & maintaining that speed to the point of flare out"

+1 on one size doesn't fit all.

I am not sure what you mean by :

" +1 on one size doesn't fit all. "

The AFM clearly outlines the operating limitations therefore a pilot must be proficient in full flap landings...correct?

In other words a proficient pilot is one who can operate the airplane throughout it's complete flight envelope when and if needed.

[DHCdriver]

From the DHC-2 AFM:

"Full Flap is only required for emergency landing in very restricted areas".

Then:

Minimum run landings may be necessary under EXDRAORDINARY circumstances.

"pilots familiar with the aircraft and experienced in short landing technique may perform minimum run landings by using full flap & reducing airspeed on the final approach to 65-68mph & maintaining that speed to the point of flare out"

+1 on one size doesn't fit all.

I am not sure what you mean by :

" +1 on one size doesn't fit all. "

The AFM clearly outlines the operating limitations therefore a pilot must be proficient in full flap landings...correct?

In other words a proficient pilot is one who can operate the airplane throughout it's complete flight envelope when and if needed.

I agree 100% Cat.

[ScurvyDog]

I thought the question was about a PA31. It's really cool how the threads on Avcanada degrade to an arguement about flaps on a beaver!

[DHCdriver]

O.K. enough with the beav and back to the Ho people.

[skybaron]

I am not sure what you mean by :

" +1 on one size doesn't fit all. "

The AFM clearly outlines the operating limitations therefore a pilot must be proficient in full flap landings...correct?

In other words a proficient pilot is one who can operate the airplane throughout it's complete flight envelope when and if needed.

Sigh.
I quoted the AFM to bring to your attention that a full flap landing with the DHC2 is not something normally carried out while approaching to land. Should one have experience, and be comfortable with a full flap landing? Of course! Without question.

Would I elect to use full flap on the -2 for every landing? Hell no. Too aggressive of a pitch down attitude, descent rate, and finally coupled with (most important IMHO) the time its going to take for me to raise those barn doors to takeoff setting on a balked approach / overshoot scenario. In the end, I'm guessing because of these reasons and many more, DHC decided to have a "landing flap" setting (one notch before full flapper).

Hence "one size doesn't fit all".

[Hedley]

When it comes to full flap discussions, I'm surprised no one has mentioned the C150 with it's 40 flap and the later C152 with 30 flap.

Many years ago, on the odd rare occasion, I would demonstrate 60 degrees of flaps on a buck fifty. Yes, 60, no typo. Fly a circuit but don't descend on final. Maintain 500 feet until the runway numbers disappear under the nose.

Apply 40 flap, nose down, and push open both doors all the way. Seriously. Cessnas do one thing well, and that's descend. Each door might be roughly equivalent to another 10 degrees of flaps. Or not. I dunno. Anyways, with 40 flap and both doors pushed open, you can pretty well hold a vertical downline above the runway numbers and the speed won't climb much with all that junk hung out in the breeze. As you enter the flare, close both doors and land.

I think it's safe to mention, now that he's retired, that a Transport Canada Inspector taught me about 60 degrees of flaps on a buck fifty, all those decades ago



This video has absolutely nothing to do with flaps or even aviation for that matter, but I kind of like the acoustic guitar playing at the beginning.

[fish4life]

The same 150 I was talking about earlier that will almost have you strike the tail if you don't use flaps was one of the early ones equipped with 40 flap... That setting is for the most part too much flap for day to day flying, if I remember correctly it was about 2100rpm to maintain 500fpm decent and 65-70kts

[ScurvyDog]

I heard when flying the Wright Flyer, all landings are done flap less. Any one know what flaps to use the Spruce Goose?

[Hedley]

the Wright Flyer

You haven't even gotten started on what they did wrong:

They did not have a Certificate of Registration.
They did not have a Certificate of Airworthiness.
They did not have a current annual.
They did not have any airframe and engine logbooks.
They did not have a compass.
They did not have a pilot's certificate of any kind.
They did not have a pilot medical.
They did not hold a valid A&P/IA certificate.

Really, given all of the above, the Wright Brothers should have been thrown in jail for quite a number of years for daring to commit the Sin of Aviation (tm). Landing flapless is pretty small beer, compared to all their many other offenses.

Spruce Goose?

Oh goodie. Can I talk about what a nutjob Hughes now? Again, given what else he did (and was accused of), flaps vs no flaps would be a fart in a windstorm for Howard Hughes.

[ScurvyDog]

Hehe I knew that would get things going hedley! Love poking the bear.

[Hedley]

I should do colour commentary, like that fat guy on football.

[iflyforpie]

The same 150 I was talking about earlier that will almost have you strike the tail if you don't use flaps was one of the early ones equipped with 40 flap... That setting is for the most part too much flap for day to day flying, if I remember correctly it was about 2100rpm to maintain 500fpm decent and 65-70kts

The problem with the 150 is, owes its design to the 140 (basic fuselage and wings) and the 170 (slotted Fowler flaps), both of which were taildraggers mainly intended to go on and off dirt or grass strips, plummeting at a steep angle over the rows of trees that would invariably be at the edge of the field.

When jets finally came around, light aircraft became more tailored to pilots who would eventually fly them. The Cherokee, with its low-wing, laminar-flow airfoil, all-moving stabilator, (relatively) high wing loading, and ornamental flaps was made perfectly for the pilot following the PAPIs in for landing. Just drive it on like you would an Ercoupe (which was incidentally designed by the same guy: Fred Weick).

In fact, if you come in too steep and a bit slow in a Cherokee, you can find yourself uncomfortably on the back of the power curve and wind up hitting obstacles or slamming down on the runway early owing to the large amount of induced drag and ineffective stabilator.

Cessnas were not designed to hold a three-degree slope with full flaps with a low power setting. Even the 206 I fly will require cruise power settings with full flap to follow the PAPIs in on the very odd occasion I am doing a straight-in to a runway that has them (but then I will usually but 20 on and 40 on short final). Four degrees (500ft at one mile) suits most single engine Cessnas much better for full flap approaches.

[PanEuropean]

I quoted the AFM to bring to your attention that a full flap landing with the DHC2 is not something normally carried out while approaching to land. Should one have experience, and be comfortable with a full flap landing? Of course! Without question.

Would I elect to use full flap on the -2 for every landing? Hell no. Too aggressive of a pitch down attitude, descent rate, and finally coupled with (most important IMHO) the time its going to take for me to raise those barn doors to takeoff setting on a balked approach / overshoot scenario. In the end, I'm guessing because of these reasons and many more, DHC decided to have a "landing flap" setting (one notch before full flapper).

I agree with Skybaron on this matter. In addition to the disadvantages that he has mentioned, there are other reasons to avoid using full flap for landing unless it is absolutely necessary. These include reduced elevator authority for pitch-up maneuvers, and an increased risk of tailplane stall in the event of any contamination being present on the leading edge of the horizontal stabilizer.

Full flap decreases the stall speed of the aircraft, thus if a crosswind is present, the crosswind component as a percentage of touchdown speed (stall speed) will increase. In strong crosswinds, this may result in directional control difficulty between the flare and the time all the aircraft weight is on the wheels.

Michael