Aileron spar lightening holes

[Bruce Fenstermacher]

Soooo Gar, if I understand you correctly, you are reporting in a thread titled aileron spar lightening holes, that George has modified his 170 with yet another modification to the original specification. Hmmm I guess there might be some tie in being that some folks have mention flaps in this discussion. You know in a few years there won't be much original left to modify on George's 170 at the rate he's going.

[flyguy]

You know in a few years there won't be much original left to modify on George's 170 at the rate he's going.

IMA TINK HYEAR IS HIS NEX MODYFICTATION

goofy rudder.jpg

[Bruce Fenstermacher]

Well it certainly is the correct color for George.

[c170b53]

Just to keep this one going here's a pic of the O/B ends of my flaps

[c170b53]

Here's the other side, I'm guessing this is the norm

[GAHorn]

Soooo Gar, if I understand you correctly, you are reporting in a thread titled aileron spar lightening holes, that George has modified his 170 with yet another modification to the original specification. Hmmm I guess there might be some tie in being that some folks have mention flaps in this discussion. You know in a few years there won't be much original left to modify on George's 170 at the rate he's going.

Just keep to the judging rules and I'll take my chances. (Cold day in Hell that I'll ever have tail feathers like that!)

Ol'Gar was simply describing the sector which determines the flap settings....and my airplane uses t he genuine Cessna part approved for a B-model.

[Bruce Fenstermacher]

Well as a judge the last two years it is my opinion that the associations judging rules need to be modified a touch. Not that your plane George would be considered a modified plane under the changes I have in mind but it would be closer. As it is it is virtually impossible to have a modified 170 of any model unless you have made an engine conversion to a larger engine and then it is automatic. My 170A which is virtually a 170B with the wrong wings, wrong year engine, wrong paint scheme, wrong interior patterns and vortex generators, still is not a modified airframe under our judging rules. But this is another subject all together.

Jim I'm afraid the lightening holes in the one end of your flap might tip the scales in a judging contest but if your running against Georges "original" example your still in the running.

I'm pretty sure I've never noticed the ends of any flaps open like yours Jim.

[GAHorn]

Cessna began to "lighten" up parts as their models gained weight thru the years. If you order new replacement outer ribs from Cessna they will have lightening holes. Both ends of both my flaps have lightening holes as they were rebuilt in the 1990's.

I agree that the judging criteria should be updated.

[wrench]

This is an interesting discussion. The 170B IPC shows LH aileron p/n 0523800 using spar p/n 0523806 and the current production Skyhawks still use this base number. I pulled spar drawing 0523806 dated 9/1/48 and it shows eight holes in the spar. My guess is that the illustration in the 170B IPC showing twenty seven holes was perhaps borrowed from another model drawing.
JT

[wrench]

Well, I need to make a correction to my first post. I see that in 1957 a revision was made to the drawing and nineteen holes were deleted from the original twenty seven leaving eight.
JT

[KG]

For what it's worth...... '53 B serial number 25431

8 holes in each aileron spar

both ends of both flaps have lightening holes

k

[170C]

Now George, regarding your not ever having tailfeathers like those in the above photo, I could understand your comment if they were GREEN or maybe white, but those are RED What give

[cbeyer]

52B SN 20472: 4 each lightening holes on both ends of both flaps.
54B SN 26354: No holes in the end ribs of the flaps.

CBeyer

[GAHorn]

Now George, regarding your not ever having tailfeathers like those in the above photo, I could understand your comment if they were GREEN or maybe white, but those are RED What give

Maybe the shape was altered by the sonic boom?

[GAHorn]

For what it's worth...... '53 B serial number 25431

8 holes in each aileron spar

both ends of both flaps have lightening holes

k

The previous comment I posted suggesting my flap end-rib lightening holes might be the result of re-build is apparently incorrect. Here is a pic from a 1952 Cessna Ad promoting the advantages of the new 1953 170-B model:

53 flap end ribs.jpg