Split Flaps in my PA-30

[Tim Puliz]

Today, while preparing for an ATP check-ride, we were performing a full-flap, stall recovery. After a nose-down recovery and retraction of the flaps, the plane seemed to be flying in an engine-out scenario. What really happened was the right fowler flap did not fully retract, but the left flap did. It looked like the right flap retracted about 1/2 way.

After landing, we were able to retract the flap fully; (once there was no pressure on the flaps). We we able to deploy and retract the flaps successfully on the ground several times at the hanger.

Does anybody have any suggestions as to what needs to be repaired/replaced?

Sincerely,
Tim Puliz
Reno, Nevada
775-742-3253

[Kristin Winter]

Tim,

Check the flap tracks themselves. Do the slots look like dogbones? If so, you need to replace one or more of the six track brackets. Next, clean the tracks and determine whether you have steel or nylon rollers. The nylons are about the same color, so you really need to check for hardness, magnetism, etc, to be sure you know what you have. Get nylon ones of you don't have them. Clean the flap tracks, but do not lube them with the nylon rollers. Look at the spring on the inboard end of the wheel well. Does that spring look like it has been there forever? If so, replace it. It helps pull the flaps up. While you are at it, there is another spring in the wing, forward of the flap actuator arm. It has likely been there forever too.

I have done all that on my twin, with the exception of replacing the flap tracks. That may be one of my next projects.

[Tim Puliz]

Thank you so much Kristin. I'm forwarding on your comments to our mechanic.
Tim

[Kristin Winter]

Tim,
If you need some Comanche specific help, I am just over the hill and across the central valley.

[N3322G]

Tim,

Exact thing happened on my ME checkride on during simulated approach to landing and go around. Thought examiner had pulled an engine. Plane was only 5 years old. Prior Twin Cos required grease on the flap tracks and the 'new' 39s had nylon rollers and did NOT require grease. So the problem was grease in December in Chicago cold where it was not supposed to be.

Hope this helps.

[Tim Puliz]

Thanks Pat.
I'll pass this on. My Mechanic is concerned because there is supposed to be a cable connecting the two flaps and is supposed to prevent this from happening.

Tim

[9089P]

Hi Tim,

While training for my commercial, I had the same thing happen during recovery from slow flight configuration. After checking the items noted above we decided to change the springs, both inboard and outboard. They had all been changed when the aircraft was painted roughly 5 years earlier. Upon opening up the flap we found that the mechanic at the paint shop had failed to properly install the cable that attaches between the spring and the flap. The cable was not in it's "track" and as a consequence it had far more drag than it should have. We put the cable in the track, problem solved.

Good luck, Don

[Tim Puliz]

Thanks Don.

I'll pass it on.

Tim

[N3322G]

Tim,

Interesting comment on the cable - have not seen that in the Twin Comanche Service manual. You might ask the mechanic where in the service manual he found that information because in the 44 years our Twin has been in the family, I have not seen or heard of this. Please be sure the mechanic is familiar enough with Twin Comanches to do this work or it may be an expensive 'repair'.

[Kristin Winter]

[Tim Puliz]

Kristen,

Thanks for the clarification. These forums have just been terrific. I hope to provide knowledge I pick up along the way to all of you!

Sincerely,

Tim Puliz

[9089P]

Hi Pat,

The "flap return cable" is item #27, figure 5-5, sketch B, on page 1G8, in my Piper service manual rev, 4/10/81. This manual is for singles but I'm confident the twins have the very same cable. I have attached a copy of the drawing.

Don

[Tim Puliz]

Don.

Thanks for the drawing. I'll forward this on to my mechanic as well. I did send him the entire PA-30 service manual a couple years ago.

Sincerely,

Tim Puliz

[N3322G]

Hey Don,

How very kind of you to go to the effort to post the diagram for everyone's benefit.

I'm familiar with the flap return cable. My concern for Tim was that someone was trying to convince him there was a cable that prevented the split flap condition and to the best of my knowledge there is no cable on a Comanche that will prevent that. I've replaced lots of parts in the years since I inherited. I have zero desire to have my most precious husband take the plane backpacking in the mountains and have a problem. He is a fine pilot in his own right but why make it any harder on him than it has to be? So in this area alone - flap tracks have been replaced and flap springs and I've personally assisted in adjusting the return cable. This stuff is why I go to annuals - you learn a lot.

As Kristin so eloquently put it, there is a misunderstanding somewhere.

[Tim Puliz]

Don, Pat:
We were confused before these posts. Thanks to both of you.

Tim Puliz