03-12-2012, 08:34 PM

Ed Lynch | Flaps

Lately, I notice that when I go to raise the flaps after takeoff, they are already halfway up. I normally use 15 flaps for takeoff, and after the gear is up, and I have accelerated to 100k, I go to raise the flaps, and they are at 10 degrees or less. Has anyone else encountered this?

I have checked the hyd fluid filter, and it is clean. My pump only runs when needed, and does not cycle. Not a problem on landing.

I suspect internal flap actuator leakage. What do you think, guys? Ed

03-13-2012, 11:33 AM


Yes Ed. My first guess would be that the fluid is leaking around the piston or thru the threads that hold the piston to the shaft. Since it is the wind blowing on the flaps that is causing the piston to move thru the fluid it is keeping the pressure up and the pump isn't cycling. Just a guess of course but I think you're right.

John J

03-13-2012, 09:44 PM

keithw | Flaps

John J I think you are correct. Ed, Quick question? Do you have Graingvill (MSP) Hyd Additive in your system? Im not a big person to recommend additives but it sure has helped my system for years and years!!!!! Keith Walljasper N80CC

03-14-2012, 12:09 PM


I agree with you Keith. I’ve been using the same additive for over 4 years now with very good results. It seems to handle minor leaks and bypasses very well. JR

03-14-2012, 07:02 PM

Ed Lynch | Flaps

Thanks, guys. I have some of that stuff, but never put it in. I'll do that before I take any other action. How much? All of it??? Ed

03-14-2012, 08:05 PM

keithw | Flaps

Hi Ed; I dont know what the instructions say, But if my memory surves me right I used a pretty good dose.!!!! Ha Ha Another words (Go your best) Drain resivor down and make sure you get it circulated. Keith I know Im not much help? (SO Go your best)

03-22-2012, 12:32 AM

mike reibling | Granville Oil

I will second or third that....

I have used Granville in all my olio's for a couple of years now and all my nitrogen leaks have gone away.

I use it as directed, 1 part granville to 8 parts oil. It does say overdosing won't hurt anything.

PS - Thanks Kieth for on Asphalt info.

07-14-2012, 08:47 PM

Ed Lynch | Flap Actuator leakage

Well, it finally happened-- my flaps would not come down for landing. Another no-flapper! My last one was when I broke a flap drive link after a "water loop" on landing; but that's another story.

This time, all I got was a lot of howling, but no motion on the flaps toward down. Worked perfectly after landing, though. So I had the cylinder rebuilt at the local hydraulics shop($50), and am just getting around to installing it. I normally would have waited until I flew the plane again to report on it, but I am doing the annual (#3 already!), and might be awhile. So I wanted to post something, so I don't keep getting "no new posts" every time I sign on! Where is everybody? In front of the air conditioner, drinking pina coladas? I hope so-I am! Ed

07-15-2012, 05:23 PM


Ed, is that the "link" outside the plane .....6" round rod that connects to the flap? I have broken 3 of those so far..... What the hey... I carry one for a spare.

07-16-2012, 12:07 PM

Ed Lynch | Flap linkage

Yep, that's the one. 5/16 rod by about 4 1/2 inches long, threaded both ends. I bought some bolts from A/C Spruce, cut off the hex head and threaded the end. I now carry a spare, too. That must be the weak link, but that's not all bad, considering how much more trouble it would be to fix the flap. Full flaps and water do not mix well for me! Now I do flaps 25. Haven't broken one since. Ed

07-16-2012, 05:53 PM


When needed, i thought 30* and then move them going on and off step , as needed. 40* got me when jack and i were doing the pre buy however, of the three, the last one bothered me the most.

Bout a year ago I was trying to take off of a lake that was very choppy. After a few bounces, aborted take off, and swing around to try again.......... Well i tried again and again aborted. For some reason the plane was very sluggish and to poor respond to the required inputs. Heading back to the nearest ramp i looked into the rear of the plane and noticed water over the floorboard. Once on land i repaired the water pump, found the leak around the gear and then noticed one of the flap links broken.

Dam, what if i tried a little harder to take off? What would a flapping flap do?

The flap position sensor is located in the center of the plane so you know where the flap tube is in relation to the piston, however we really dont know where the flaps are.

Would it be worth investing in a position sensor for both flaps or a wire sensor connected to the link?

07-17-2012, 03:50 PM


Flap Position .. After I bought N521GR (2005) the first thing I changed was the ridiculous flap indicator that ran off a 16-turn potentiometer. I installed a ‘Ray Allen’ indicator for the right side flap and a simple mechanical ‘wire and spring’ tied to a ‘horizontal bar’ indicator for the left flap. I like the mechanical indicator best however when it comes to flap position, having both provides a greater level of confidence and safety.


07-19-2012, 05:57 PM


At the least, one should add "full flaps up...down" To the checklist before taking off.

O yea, and looking to see if both flaps are moving......

07-22-2012, 05:22 PM

Ed Lynch | "Flapping Flaps"

If there is ANY doubt as to whether or not you have damaged the flaps during water work-takeoff or landing- you should verify flap position visually. A broken flap link will allow that flap to hang down vertically, and you can see that from the cockpit. As airspeed increases, that flap will retract itself due to airload, and if you manage to get airborne at all in that configuration, the aircraft will roll uncontrollably into the broken side- not a great situation! So retract the working flap, and do a no-flap takeoff(+20 extra knots), and landing. Ed

07-23-2012, 02:50 PM

Larry Brunzlick

I think I have an idea of what you are trying to describe about the wire and spring tied to a horizontal bar indicator, but could you elaborate a little more perhaps post some pictures.

Does the mechanical sensor make direct contact with the flap? And does it just tell you if the flap is all the way up?

Larry Brunzlick

07-24-2012, 12:01 PM


Howdy Larry .. For the right side flap indicator I used a Ray Allen ‘pos12’ sensor and a Ray Allen RP3 indicator. For the left side (horizontal flap indicator) I used stainless steel fishing leader in a stainless steel cable shield (similar to a bicycle front brake cable shield). The cable is connected to a lightweight spring and remains taught while able to move freely through the shield. Both indicators connect to their corresponding flap tube with a made-up ‘L’ shaped aluminum connector arm attached to the tube with a standard ‘hose clamp’. The length of the arm depends on the travel needed for an accurate reading on the indicator. By the way you will notice 2 ‘fuel transfer’ lights in the picture of the right side flap indicator. These LED indicator lights flash anytime fuel is being transferred reminding me of the transfer operation. This helps me avoid transferring too much fuel as it is EASY to forget you are transferring. In my Seawind, when the receiving fuel tank is full the excess fuel overflows into the corresponding auxiliary fuel tank .. Not good. Hope this helps


07-25-2012, 08:44 PM


I think i am going to do something with the ray allen sensor on each flap tied into my effis....

07-26-2012, 12:05 PM


Keep in mind, if you are going to put a sensor on each of the flaps with the intention of knowing when there is a flapdrive-rod failure, you will need to put the sensor attach point on the flap itself. Whatever you use to sense position will need to have the same length of throw as the leading edge of the flap, about four to five inches unless you find a way to attach the sensor to the flap hinge right down by the bolt. Putting them on the tubes or even on the drive cleavis out in the wheel well will only show you where the drive mechanism is, even if the rod fails.

See you guys soon at the Splash In.

John J

07-27-2012, 09:30 PM

Tony Jurcan

Posibly a waterproof 5000 ohm linear potentiometer attached between the wing and flap. if there is one available.

07-29-2012, 09:20 PM

keithw | Flaps

Excellent Observation (John J. Planemakers) We dont want to know where the flap tube is---We want to know where the flap iis Thanks Keith N80CC

07-30-2012, 02:04 PM


In addition to my flap position sensors I utilize a video system (3-cams) that gives me a view of my landing gear and both flaps. JR