mikesalman Posted July 11, 2013 Report Posted July 11, 2013 Hi folks I just had my manual flaps worked on because they would leak back up half way down the runway or in the pattern. My A&P said he had to re-build my pump, now they hold just fine but when I retract them they spring back up too fast like going from full flaps to no flaps in 1/2 a second. The scary part is if I have to do a go around I don't want my flaps retracting that fast so close to the ground, I can't stop them half way the just retract too fast. Any advise on how to slow them down would be really appreciated. Quote
47U Posted July 11, 2013 Report Posted July 11, 2013 There's an adjustment screw on the flap pump body. Loosen the jam nut and turn the screw clockwise to slow the rate of retraction. Maintenance book says 8-12 seconds. Flap Pump.pdf 2 Quote
Wildhorsesracing Posted July 11, 2013 Report Posted July 11, 2013 FWIW - I don't retract my manual flaps until I reach Vx (80 mph) and that usually doesn't happen until I am well off the runway and have sufficient altitude. YMMV Quote
rahawk Posted July 11, 2013 Report Posted July 11, 2013 My mechanic and I just rebuild my flap pump, and the adjustment is very senitive. We set the flaps to fully retract in 10 seconds, and it works very well. Also rebuilt the parking brake mechanism, as it had developed a slow leak. I cannot imagine rebuilding the parking brake mechanism without the avionic access panels.... 1 Quote
orionflt Posted July 11, 2013 Report Posted July 11, 2013 Thats a great breakdown of the pump, thanks I'll add that to my libary. Mike, you shoud be able to make the adjustment to the restrictor valve yourself, should only take a few minutes and a coupe of cycles till you get it reset. 1 Quote
N201MKTurbo Posted July 12, 2013 Report Posted July 12, 2013 Just remember that they will come up faster when flying then they will on the ground. 1 Quote
mikesalman Posted July 12, 2013 Author Report Posted July 12, 2013 There's an adjustment screw on the flap pump body. Loosen the jam nut and turn the screw clockwise to slow the rate of retraction. Maintenance book says 8-12 seconds. Thanks, that diagram is great I appreciate the advice. Quote
mikesalman Posted July 12, 2013 Author Report Posted July 12, 2013 FWIW - I don't retract my manual flaps until I reach Vx (80 mph) and that usually doesn't happen until I am well off the runway and have sufficient altitude. YMMV Same here, but what scares me is a missed approach with full flaps so close to the ground. When you retract the flaps they are up from full flaps to no flaps in less than a second. Quote
treebobboy Posted July 12, 2013 Report Posted July 12, 2013 I was always taught, and have always taught, to fly your approach with 50% flaps. When landing is assured, then you go to 100% flaps. If you are not comfortable changing flap settings after you break out at 200 feet, then land with 50% flaps. The Mooney lands just fine with takeoff flap settings. The big thing on a go around is to get the biggest drag item stowed as quickly as possible, which is the landing gear. The flaps cause drag, but nothing like the gear. 2 Quote
mikesalman Posted July 12, 2013 Author Report Posted July 12, 2013 I guess I'm still a little scared of my new to me M20F I only have 19 hours in it. And I just got my PPL last Sept. with 99% of my flying in a 2004 Cessna 172. I guess I just want everything to be perfect to minimize being a statistic, better safe than sorry. Everything is different in a Mooney and at 46 you tend to learn a lot slower than when you were younger. 1 Quote
AmigOne Posted July 12, 2013 Report Posted July 12, 2013 For me 100% flaps in my C is too much. I take off and land with the t/o flap setting, on landing that will ensure that I will touch down on the mains with normal back pressure and then be able to lower the nose gear slowly while I still have elevator control. I like to judge my landings on how well I hit the speed over the threshold and how softly that nose gear comes down. And I don't like to use the brakes until the last moment, of course I'm based on a 5000 ft runway which makes it easier. Also there are no significant obstructions at either end and I also have VASI lights. 1 Quote
stevesm20b Posted July 12, 2013 Report Posted July 12, 2013 There is no pump or diaphragm with the manual flaps. Its all mechanical linkage. Manual flaps have a lever that you raise up and down. If the flaps are coming up to fast, move the lever slower. 1 Quote
carusoam Posted July 12, 2013 Report Posted July 12, 2013 Steve, In the 65' C, there is a real hydraulic hand pump. Pressure relief is via a valve with a screw setting for rate. Best regards, -a- Quote
mikesalman Posted July 13, 2013 Author Report Posted July 13, 2013 O.K. my mistake for calling it manual flaps. Hydraulic hand pump flaps. I never knew there was a third type of flaps since I was only exposed to the electric flaps in a 2004 Cessna 172 and My 1968 M20F with the manual flaps. Oops sorry hydraulic hand pump flaps. I'm still learning :-) Quote
carusoam Posted July 13, 2013 Report Posted July 13, 2013 Mike, I just found out that the B's manual flaps weren't hydraulic.... I added the extra detail to be clear. Best regards, -a- 1 Quote
stevesm20b Posted July 14, 2013 Report Posted July 14, 2013 I don't know why Mooney ever went to the hydraulic flaps. The mechanical flaps always worked and was a much simpler design. Quote
mikesalman Posted July 16, 2013 Author Report Posted July 16, 2013 Thanks for the link 47U. Today I went to the hanger and removed over 60 screws from the belly of my 68 M20F to reach the hydraulic pump for my flaps. I could not access it from the small inspection cover. It now takes about 14 seconds to go from full flaps to no flaps. I know that's a little slower than the 8 to 12 seconds recommended it just got really slow that last 1/4 coming up. I may go flying tomorrow if weather and work permits and try it out. Quote
jetdriven Posted July 16, 2013 Report Posted July 16, 2013 For me 100% flaps in my C is too much. I take off and land with the t/o flap setting, on landing that will ensure that I will touch down on the mains with normal back pressure and then be able to lower the nose gear slowly while I still have elevator control. I like to judge my landings on how well I hit the speed over the threshold and how softly that nose gear comes down. And I don't like to use the brakes until the last moment, of course I'm based on a 5000 ft runway which makes it easier. Also there are no significant obstructions at either end and I also have VASI lights. The airplane lands normally with full flaps. It also lands at a slower speed and thus less wear on brakes and tires. If you are having trouble landing on the mains first with full flaps perhaps some practice will fix that. 1 Quote
flyingvee201 Posted July 31, 2013 Report Posted July 31, 2013 There is no pump or diaphragm with the manual flaps. Its all mechanical linkage. Manual flaps have a lever that you raise up and down. If the flaps are coming up to fast, move the lever slower. Mine also come up pretty quick especially when you are doing a go around and have full flaps! I tried your technique and slowly moving the flap control lever until I saw felt the flaps starting to retract. IT WORKED! I left it in that position until the flaps were completely retracted, then I raised the lever completely and tucked away the flap handle. This is my new technique now for retracting the flaps! thanks!! Quote
carusoam Posted July 31, 2013 Report Posted July 31, 2013 Temporary new fix right??? Adjusting the bleed valve properly would be a tried and true better solution. Distractions during the go-around can lead to disaster... The B has "really" mechanical flaps... (who told me this???) The C has hydraulicly actuated mechanical flaps... So the C pilot probably can't use the B pilots technique very easily.... Or did I just miss something... Best regards, -a- Quote
flyingvee201 Posted August 1, 2013 Report Posted August 1, 2013 Temporary new fix right??? Adjusting the bleed valve properly would be a tried and true better solution. Distractions during the go-around can lead to disaster... The B has "really" mechanical flaps... (who told me this???) The C has hydraulicly actuated mechanical flaps... So the C pilot probably can't use the B pilots technique very easily.... Or did I just miss something... Best regards, -a- Yes, this is temporary (at least for my plane). I have it on my list to adjust it during the annual in a couple weeks. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.