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Brake pedal position issue


Pinecone

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When I did my transition training in my plane, I noticed that the brake pedals are rotated aft too far.  It is impossible to not get some brake with rudder application until I carefully position my toes below the brake pedals.

Airplane is now in annual and this was a squawk.  But the shop is telling me that the pushrods are adjusted as short as they can go.

Has anyone run into this before?  What was wrong?  How was it handled?

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1 hour ago, Pinecone said:

When I did my transition training in my plane, I noticed that the brake pedals are rotated aft too far.  It is impossible to not get some brake with rudder application until I carefully position my toes below the brake pedals.

Airplane is now in annual and this was a squawk.  But the shop is telling me that the pushrods are adjusted as short as they can go.

Has anyone run into this before?  What was wrong?  How was it handled?

Are there extensions on them? We have some threads on those with pictures. Some rotate the pedals a little if I recall.

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I would get used to repositioning my foot.

I assume that shorter rods could be fabricated, but be very careful if you do that, be sure the brake still has full travel, rudder too.

‘I’m about as close to 50 percentile as anyone could get. I position my seat as far forward as it can go to get full rudder travel without stretching.

I would like to have extensions. I bring that up as if your 70” or so tall and don’t have your seat way forward maybe you do have extensions

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38 minutes ago, A64Pilot said:

I would like to have extensions. I bring that up as if your 70” or so tall and don’t have your seat way forward maybe you do have extensions

It's more about the length of your legs than total height. My father in law was 6" shorter than me, and the inseam of his pants was 26" compared to my preferred 33".

FWIW, I'm 5'11" (71" as used above), and I fly my C from the middle seat position (there are only 3 positions that lock in place).

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Back in the day as I was in the first AH-64 unit, (3-6 Cav) we went through a lot of testing etc. One of those things was USAARL, (ArmyMedical) measured every one of us, army length, reach, leg length etc. even how far apart our eyes were. Of course the average of those were known ,but I guess not the average pilot.

‘Anyway I was almost exactly average for US Male population in almost every respect.

Oh, one thing that surprised me in that study was that almost all the height difference in people is leg length. As the AH-64 had a helmet sight that precisely tracked helmet position, we had to sit at “design eye height”. We had a bore sight reticle unit mounted on the glare shield, we had to adjust seat height until you could look into it and a bullseye was perfectly centered. Difference in seat height from a 6’6” guy and a 5’6” guy was only an inch or so, but their height was a whole foot different.

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13 minutes ago, Pinecone said:

I suspect extensions.

But here are some pictures.

brake 2.JPEG

brake linkage.jpg

Besides cutting the threads longer in those rods in the master cylinder, look at the bell crank they attach to, there is another rod, I feel sure either shorter or adjustable rods could be fitted there.

If you have the treads cut longer on the Master cylinder, be sure to replace the O-rings and Statoseal

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The 3” extensions affect pedal angle moving the top of the pedals aft.

My 1994 M20J has different master cylinders, but it looks looks like the technique I used would work on yours. Leave everything connected. Loosen the jam nut. Then you can rotate the shaft. There is a lot of leverage and I didn’t need to turn it more than a couple of turns. More info here…

 

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27 minutes ago, JimB said:

And how did that make you feel? :D

At 5'6, I'm anything but average! :rolleyes:

Just thought it funny, they didn’t measure everything.

Now I say I’m a fat version of 50th percentile.

I lost almost an inch in torn up knees, but think I got most back with the fake versions, I’m no longer bow legged.

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6 hours ago, Pinecone said:

When I did my transition training in my plane, I noticed that the brake pedals are rotated aft too far.  It is impossible to not get some brake with rudder application until I carefully position my toes below the brake pedals.

Airplane is now in annual and this was a squawk.  But the shop is telling me that the pushrods are adjusted as short as they can go.

Has anyone run into this before?  What was wrong?  How was it handled?

Check your logbooks. When the Encore mod was done and presumably new CM2000-5 Master cylinders were installed, Mooney sold them in a kit p/n 940076-000 that includes two links p/n 850080-001 that extend the throw of pedal to correct exactly what you describe. (There are also a couple of new bell cranks spec's for the conversion separate than the links which appear to be present) I test flew another converted Encore, right out the conversion process, where it turned out they only installed the new master cylinders without the additional links and it had the same issue you describe; only corrected when they installed the missing part I referred them too. I am guessing same thing with yours.

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8 hours ago, kortopates said:

Check your logbooks. When the Encore mod was done and presumably new CM2000-5 Master cylinders were installed, Mooney sold them in a kit p/n 940076-000 that includes two links p/n 850080-001 that extend the throw of pedal to correct exactly what you describe. (There are also a couple of new bell cranks spec's for the conversion separate than the links which appear to be present) I test flew another converted Encore, right out the conversion process, where it turned out they only installed the new master cylinders without the additional links and it had the same issue you describe; only corrected when they installed the missing part I referred them too. I am guessing same thing with yours.

Hey paul you only need these after the encore conversion right? Original 252 doesn’t need them?

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13 hours ago, Will.iam said:

Hey paul you only need these after the encore conversion right? Original 252 doesn’t need them?

correct, but it's more accurate to say original mid-body master cylinders don't need them. The original master cylinders are no longer available so many go to the current, larger capacity, master cylinders which do need them regardless if one goes to the long body calipers.

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I got one of the mentioned parts from Lasar.  But they only had one.  This link is adjustable.  It has a fixed clevis at one end and a threads shank rod end at the other.  The minimum length is 5.15" hole center to hole center.

Loewen's thought they had one, but it is a fixed length one (clevis on each end) that is 6" hole center to hole center. Which appears to be what is currently installed.

The good news is, Mooney has the parts and can fabricate one.  The bad news is, about $600 EACH.  WTF?!  It is a rod end ($34.50 from Aircraft Spruce), a clevis ($19) and about 4.5" of 4130 tubing (maybe $1).  And 30 minutes labor, not including painting.  It does look like the modify the clevis slightly, which is the only thing from stopping me from making one.  I have a TIG welder and know how to use it. :D

Oh well.

69267419748__A35288A9-B814-4270-930A-5ED5FF405E0D.JPG

69267425534__C0B386E3-5CF4-4207-8EF0-2B77D936C1BB.JPG

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I’d still make my own the clevis should be easy to bend once heated, if your real concerned dye penetrate it after bending.

This is what OPP is for in my opinion. Did Mooney give you a delivery date?

Actually I remembered, I know that clevis is made that way, we used it on the control cable connections to the Thrush throttle lever quadrant.

Worst case call Thrush Aircraft parts and buy a couple, back when I ran it we weren’t too bad on parts prices, maybe that hasn’t changed.

Ones we used were threaded as I think that one may be, looks like there is a hole in it anyway.

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Do you have a contact at Thrush for the modified clevis?   Mooney quoted 4 - 5 weeks for the part.  Not a bit rush to me.

It may be threaded, but it is inserted into the tubing and welded.

Another option is to pull one link off my airplane (or buy one of the fixed links) and cut it in half.  Two short pieces of the proper thickness tubing (3/8 OK, threaded 14-28 inside and two rod ends, and I have two adjustable links. :D

 

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Just call them Mon morning and ask for parts (229) 883-1440, that’s the receptionist, they don’t open until 8 AM EST, the floor which includes parts 7 AM but I don’t remember parts number.

Say it’s for a 1997 S2R-T34, I’m sure they haven’t changed, but I’m certain in 97 it’s what I remembered, it’s the same for all Thrush’s but the T-34 is the most popular model. There are three cables, throttle, prop and condition lever all use the same clevis, so say throttle I guess, the clevis connects to the throttle quadrant.

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What are the odds? I had to send GE a pic of the throttle lever quadrant so I had a pic that I found, the clevis is easy to see.

It’s not modified it’s made that way, the gold color is cad plate of course, so may want fresh air if your welding on it.

If the price isn’t good ask for the part number 95% sure it’s the actual part number not a Thrush part number, we didn’t do that unless we did modify it.

 

AEEF8317-F0C1-4A65-871D-5ABF9896232D.jpeg

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