I am getting my 52 170 ser #20292 closed up by the maintenance shop. It was pointed out to me to-day that the rear horizontal bulkhead(pn 0512118-7 is missing the reinforcement doubler on the bulkhead part numbers 0512118-9 and -8. I checked the 170A parts book and it looks like it doesnot have these.My horizontal bulkhead looks original, and looks like it was never installed. I have checked with the L-19 people and they say no such thing on a L-19. Does anyone have a information on the doulbers , as the shop says the can fabricate some but need to know what thickness the material should be.
In the B model parts catalog figure 25, page 48, item numbers 21 and 22 show the doublers that the shop calls out for. iwantcessnaparts.com lists them, one for 50.76 and one for 72.00. I would just have them make them, I have measured them before at .032". Hope this helps. nick
Hi Nick,
Thanks for the reply. Thats just what I need as the shop can make it up out of .032 for far far less $$. This form just paid for another year or two worth of menbership fees !!! Any chance you or someone out there can sent me the measurements of there size ?
My plane is also missing the two bulkhead reinforcement doublers shown on fig. 25-21 and 25-22. (p/n 0512118-9 and 0512118-8). Anybody out there with their horizontal stab off that could measure or photograph these parts for me? There are at least three different threads here in which guys mention that these doublers are missing. Must all be planes which rolled off the assembly line on a Monday.
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n2582d wrote:My plane is also missing the two bulkhead reinforcement doublers shown on fig. 25-21 and 25-22. (p/n 0512118-9 and 0512118-8). Anybody out there with their horizontal stab off that could measure or photograph these parts for me? There are at least three different threads here in which guys mention that these doublers are missing. Must all be planes which rolled off the assembly line on a Monday.
What's your serial Gary? The OP serial was close to the beginning of the B model serial range. Perhaps Cessna had a back log of A model tail cones already assembled without these doublers and didn't add them retroactively.
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Bruce Fenstermacher, Past President, TIC170A
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Why would you fab and install something that was never there? I went through this a couple years ago and came to the conclusion that Cessna simply failed to provide a serial number break for items 21 and 22. If you look at Figure 65A you can understand why a doubler might be installed there. If you really want it to look like Figure 25 be sure to drill some 1/4 inch holes through the angle stiffeners-that way the doubler can make up the strength you just lost.
Cessnut,
Thanks for the explanation. I didn’t understand what you meant by “regular tailwheel steering” in your earlier post. That makes perfect sense now looking at Fig. 65A. Those two dots on the reinforcements are holes, not rivets. My ‘52 model is s/n 20734 so it doesn’t have the additional pulleys and steering cables that the later year B models have. My (incorrect) thinking was that the reinforcement was to strengthen the tail cone for yaw loads. Being a former A-300 freightdog, I’m a bit sensitive about tails wagging when they shouldn’t!
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