The other day I was flying a 172 with a CFI and at 110 knts he wanted me to put out 10 degrees of flap, which I did reluctantly. when the flaps came out I did not re-trim right away so the nose would pitch up and let the airspeed come down to the white arc. the CFI didn't like that. Is this common?? I always respected the white arc when flying, but I also like to fly final about 55 knots in the 172 that way when I get to the numbers I can be done flying and not use 3k + of runway.

I would think if you were on a check ride and did that you just got busted!!
Maybe should of questioned his logic on trying to break the aircraft? Rules! Approved operating procedures??

Seems weird to ask you to disregard the manufacture's Vfe? I'd say no and cite the POH where it is pretty clearly stated. Maybe it was a test to see if you would do it or not?

I believe starting in the late 70's, the POH states that 10° of flaps at or below 110KIAS is approved. So depending on your year, it may be okay. BUT, there are far better ways of slowing a plane down IMO.

What year/model 172?

I was thinking along those lines. he told me twice and after I pulled back to slow the plane down after the first time. then he said it again so I asked if he cared about ripping the flaps off. replied oh don't worry about that they won't get ripped off. they will slow the plane down. I like to get him sidetracked when I get to land so I can do it how I feel comfortable. nice and slow using power to control where I am going to hit the runway.

Find a new instructor.

Maybe they won't come off this time but over time you will be paying some repairs, I would not so politely tell him where to go and get a different CFI.

its a 78 N model. I am not using him as a CFI I am just flying his plane and he now has lost his medical temporarily so I am getting to build time cheap.

I was wondering about the 10 deg of flaps at that airspeed. but i feel that it isn't a good idea to do besides when flying the 170 I NEVER pulled flaps on till I was down to 75 or so and then they came in fast to 40 deg.

Tell him, nay, remind him that according to some of your high time friends putting flaps out at high speeds does nothing except prematurely wear out the rollers and bushings. If he wants to save money slow the damn thing down first.

cstolaircraft, don't misunderstand the top of the white arc. The top or Vfe is the maximum speed at which you can safely set full flaps. For instance, in my C206, as per POH (and placarded), while the Vfe or top of the white arc is 100 kts, the first notch of flaps can be set at 140 kts. Check your POH for that speed in your aircraft. It will definitively be higher than Vfe.

The 172N POH says for the Vfe of 85 KIAS in the remarks "Do not exceed this speed with flaps down.". Seems to me If the flaps aren't all the way up, they're down.

After having flaps stick while on floats on a 5000+ MSL lake in BC some years back, and paying to have cracked flap brackets replaced, I have become much more gentle on use of the flaps.

he is a high time CFI and has every rating besides lighter then air and tilt rotor. and I think that he is so engrained in how to fly a plane that he forgets that there are those of us who aren't used to 5000 ft of runway and feel quite comfortable flying slow on final and flying the wing.

PatínLoco wrote:cstolaircraft, don't misunderstand the top of the white arc.

I haven't flown a 172 in a couple years, but I just checked the POH for the SP that I used to fly. 110 knots on first notch and the white arc is only drawn to 85. As PatínLoco (whose name still amuses me) says, white arc and first notch can be different.

Looking at the POH for the N model in question, no such distinction is made. It's noted as 85 knots max.

The definitive answer for your question can be found in the flight manual for the aircraft you're flying. If you're flying this thing regularly, it might be wise to actually drag that thing out and READ it.....there is generally some useful information in those things.

MTV

WilgaBeast wrote:Find a new instructor.

+1

rw2 wrote:

PatínLoco wrote:cstolaircraft, don't misunderstand the top of the white arc.

I haven't flown a 172 in a couple years, but I just checked the POH for the SP that I used to fly. 110 knots on first notch and the white arc is only drawn to 85. As PatínLoco (whose name still amuses me) says, white arc and first notch can be different.

rw2, in my country, patín loco means "crazy tail wheel"

Eduardo

78 172N POH says max speed with flaps deployed is 85 kts which is the Vfe speed.

it also says something about not taking off with more then 10 deg of flaps. Just wondering anyone try using 20 before??? 20 worked great for the 170.

Just to be different here and probably annoy the by the book types......
You are flying cheap. He pays for the brackets and hardware. Fly it his way on those brief times he wants. Then fly it your way the rest of the time. Cheap is good. Caution is good. Too much caution might mean less flying. Flying is important. See ya.

You most likely will not see any roller damage.
What you will notice is the trailing edge of the flap will develop little cracks from the rivets and possibly deform the bottom corrugated skin mostly on the pilot side. If you check I will bet on there being a few cracks already there. In later years most Cessnas have a trailing edge bulb which helps with this and lets you put in the first notch of flap a little sooner.

20 degrees for takeoff while fairly light will help.
At full gross maybe no so much.

Bottom line. If its his plane fly it like he wants you to fly, unless it puts you in danger!

If it has the cracks bring this to his attention.