Thorp Air Command - T18.net

The canopy latch on my Thorp was not the latch described in the plans and the latch has been completely removed from the airplane. Does anyone out there have pics of their canopy latch they installed AFTER the airplane was built/completed. What kind of holding/clamping force do I need? I have seen some that hold 350#, 700#, etc. Heres a picture of what Ihad in mind. It will require some modifications to attach it to the roll bar but its the best thing I've come up with so far.

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Canopy Latch

If you're not going with the "original latch" then a simple over center latch will work. Try to keep it small. A version or modified one of your pic will work. The NL's have write ups for this type of latch.

RB

Thats a good idea. I completely forgot to search the NL's for this info before posting the question. Thanks Rich.

I have several of these laying around, they're small and work great as canopy latches.

Ryan if you would like one I can send it up.

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Lee Walton
Houston, TX
N51863,N118LW
KEFD

I have a similar one to that Lee, and like them - one each side mounted at the bottom of the roll bar

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Fraser MacPhee
N926WM
Serial #279-1
Angel Fire, NM (KAXX)

I bought these exact latches at Home Depot yesterday but when I got home I became worried they a) wouldn't be strong enough to hold the canopy closed and b) that the reach of the catching hook may be too short. I guess since Fraser has used them, that should be good enough for real world testing.

Fraser, would you be comfortable with just one of these hooks at the top of the canopy, or is 2 your minimum?

You ever try to open the canopy in flight. I tried it once and could only manage to get my little finger in the opening. When I do a run-up the canopy slams shut from the back pressure. You do not need a 700 pound rated latch, trust me. Bob's and my canopy latch is in the newsletter some where including a drawing.

Ryan if you choose to use that latch you only need one. I used one on N4588 it holds just fine.

As Bill pointed out the negative pressure on the canopy pushes it closed in flight anyhow.

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Lee Walton
Houston, TX
N51863,N118LW
KEFD

OK well that anwers that. Thanks again fellas.

Hi
I'm actually looking for a canopy latch as well and I have one in mind ...It's on a Thorp that belongs to a forum member here and I was going to contact him and ask him what kind it is...I will let you know when I find out ....or if he reads this and wants to offer the info ...I just didn't want to overstep.
jamie

Hello Everyone purchased a T-18 a few months back from california and just getting it registered in canada ,anyone out there with canadian machines that have come up with a canopy latch design to be accessed from the outside ,canadian regulation thanks ideas or pictures would be a great help

The Thorp canopy latch works very well
I had mine made up, was not cheap but works and the inspector was happy
Concrats on your purchase it really is a fun plane

Refer to your blue prints. Thorp specified canopy latch opens from outside as well as inside.

Tom Hunter
805-202-4261
http://aprs.fi/?call=N18XT

*** admin posted for Tom Hunter ***

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Forum Administrator

I have a complete set of drawings for a T-18 canopy latch with I/S and O/S handles I would be happy to send you. I have been flying my T-18 for 31 years and have never had any trouble with the latch. I rigged a setup so the latch can be locked from the O/S with a small padlock. I will have to go to town to make copies and that will take a few days.

Steve Hawley, N9008Z Bull Swamp, South Carolina

*** admin posted for Steve Hawley ***

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Forum Administrator

Making the Thorp latch is not difficult. Go to KINKOS and make copies of the drawings for the latch. Cut them out and use them as templates. Trace the parts out and center punch the hole locations. Scripe the bend lines. Cut the parts out...cut out more than one of the steel flat parts, one for the trash, one for the A/C. Using a bench vise and a torch, bend the steel parts. The handles and other aluminun parts can be made using only a band saw, disc sander and a Scotch Brite wheel on your grinder. I believe I did a write up for the NL a few issues back, complete with pics of the finished latch on the A/C. The cost to make the parts is minimal...about $10.00.

The hard part is having the nerve to drill all the holes in the canopy ! [:0]

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