336 windshield replacement
 

Hello,
We are about to order a windshield for our 336. Has anybody replaced the stock windshield (.187" thick) with a 337 windshield (.250" thick)??

Thanks in advance for the input!!
Steve

Looking into windshield history
 

Do you have a doc or other showing the original thickness of the 336 windshields?

I'm doing some research.

It seems the original windshields may have been thinner, but I am looking for history.

Early on, the windshield center strap served to:

1. Mounting for the then universal through-windshield temp probe, and
2. To hold the then-universal wet compass.

There was nothing else at the time except a remote compass.

Both compass and temp have since been commonly-replaced by vertical card compass and digital temp probe.

3. It MAY have also been the best way to get clear plexiglas was to make it thinner.

4. Also, older plastics would inevitably become brittle and hazy over time.

Modern acrylic windshields are apparently made with natural gas and are totally inert. Essentially un affected by sun/UV nor age.

---

Around 1973-76 (?) Cessna stopped making TWO 337 airframes and consolidated to one ''pressurized-style" airframe: Split door, no rear cargo door, 5 seats, smaller round windows easier to seal for pressurization, simpler two-tank design, etc. One could get this airframe pressurized or not.

At that point the much-debated center strap WAS clearly widened to become part of the airframe, as was perhaps needed for pressurized models to help retain windshield.

Pretty much every other cessna already has an option to remove the center strap, but nobody seems to have formalized that for the 337, although a common-practice.

I am in process of replacing all windows in my 336. It had a 0.250" windshield - I am putting in the OEM 0.187" thick. The 0.25" will fit, but there is not clearance in the channels for felt edging and Presstite sealant. The 0.25" on mine was installed 100% bedded in silicone - it looked fine externally. Now I am dealing with the nightmare of cleaning the channels to restore it after the windshield was removed.

Where did you get your replacement windshield and was there any wait getting it? I'm thinking about having the windshield replaced in the upcoming annual.

I have a '77 337G, SN 1795, and the only spec I'm pulling up for PN 1513770-1 is .250" thick. The maintenance manual does not have any reference towards thickness.

So mine is a 1963 336, Windshield P/N 1413702-1, got it from Great Lakes. They said 4 weeks lead time, but it arrived in 1 week. With regards to thickness, I have found no references in the parts catalog or maintenance manual to thickness - only going by the PMA parts that Great Lakes and LP Aero sell - their windshields for the 336 are 3/16". My windshield is out of aircraft now and it is clear that the channels are not sized for 0.25 thickness with felt as shown in the maintenance manual.

Thanks for the info!

Confirms original design used thinner plexiglas
 

Another clue in "The great Center Strap debate!"

Windows done
 

I finally got the windshield and vent window done. It took longer than I expected as I kept getting redirected to other projects. We got the windows from Great Lakes.

Now to order the side windows!!
Steve

Looks great Steve!

Mine need to be done, but it will be a year from now.

My gosh, that looks great!