HC-11 Flap Actuator compressed stroke measurement

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Artairman
Posts: 2
Joined: Fri Feb 10, 2023 3:25 am

Does anyone happen to have his flap actuator cylinder out/available for a measurement? I am looking for a measurement between the face of the cylinder and the end of the shiny piston in the maximum compressed position (photo attached).
I had the actuator overhauled 3 years back and have lost some flap extension since, and I want to make sure there is no internal restriction preventing maximum compression of the rod into the cylinder, before I go messing with any other adjustments. Thanks.
Doug Johnson
N654DM
2150hrs
Attachments
Max flap actuator retraction measurement N654DM trimmed.jpg
Max flap actuator retraction measurement N654DM trimmed.jpg (232.53 KiB) Viewed 3463 times
George Wehrung
Posts: 213
Joined: Tue Nov 22, 2022 3:56 pm
Location: KMRH

I would hope that Brad might have one of those out for measurements?


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Roxannezavala
Posts: 13
Joined: Thu Feb 02, 2023 1:25 pm

Doug,

I sent you an email with a picture of measurements. Let me know if this helps.

Roxanne
Artairman
Posts: 2
Joined: Fri Feb 10, 2023 3:25 am

Got measurements and pics from Roxanne and Bob Pastusek. Looks like the retraction was acceptable, so likely that the rod-end bearing was not re-positioned correctly after it was rebuilt. Fixed that today which got me a full flap down travel of 35.5 degrees (using full up as zero). That added about 4.5 degrees of travel down on the flaps. Thanks, everyone.

On another note, how many of you installed a restrictor plug inside the hydraulic flap actuator tube to limit the extension of the piston? I know there had been some discussion about that years back, but just wondering how many of you actually did the mod?
Doug J
George Wehrung
Posts: 213
Joined: Tue Nov 22, 2022 3:56 pm
Location: KMRH

That’s a Bob P question


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Tom Sullivan
Posts: 80
Joined: Mon Nov 28, 2022 2:33 pm

I installed a restrictor on two IVPT's externally. It is a sleeve that slides over the shaft fairly snugly before the jamb nut is installed. I determined the length of the restrictor sleeve by operating the system to the limits without hydraulic pressure. Both planes needed the exact same length restrictor.

Tom
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