Re: CAF Centex Wing P-39 News
Tue Aug 21, 2012 3:41 pm
I keep having to apologize for the long times between posts, but keeping a hangar with a dozen planes running smoothly really keeps me hopping!
The Centex P-39 project is moving ahead again. We were rolling right along, attaching the new wing leading edge skins when a volunteer made a horrible mistake. The skins were correctly drilled for attachment to the upper spar and were held in place with draw Clecos. Then, unsupervised, a volunteer drilled the skins for attachment to the ribs. Looked like about the time he finished drilling all of the holes, he realized that the skin wasn't completely tight around the ribs and the lower spar. So, he pulled the skin into the correct position, nice and tight and started drilling again! Both of the skin sections and all of the ribs were ruined... The skins along the rib lines looked like a perforated postage stamp.
A little knowledge and a well intentioned volunteer are a very dangerous combination.
I set about making molds to press new ribs when a gentlemen visited the hangar and told me about a business in Australia that restores warbirds. I did some Internet sleuthing and tracked them down. To my amazement, they had a factory fresh set of ribs and the forms to make the wing skins! The ribs and a set of skins were shipped to me last week and we're anxiously awaiting them at the Cobra Den.
I have SEVERELY limited the personnel who can work on the plane now. Only trained, licensed mechanics will be involved. We did run it last week for a while to get it hot for an oil and coolant change change. Sure was good to hear that Allison fire up again. We are putting the finishing touches on a flap skin and will be ready to rock when the package arrives from down under!
I'll post photos of the progress.
Thanks!
The Centex P-39 project is moving ahead again. We were rolling right along, attaching the new wing leading edge skins when a volunteer made a horrible mistake. The skins were correctly drilled for attachment to the upper spar and were held in place with draw Clecos. Then, unsupervised, a volunteer drilled the skins for attachment to the ribs. Looked like about the time he finished drilling all of the holes, he realized that the skin wasn't completely tight around the ribs and the lower spar. So, he pulled the skin into the correct position, nice and tight and started drilling again! Both of the skin sections and all of the ribs were ruined... The skins along the rib lines looked like a perforated postage stamp.
A little knowledge and a well intentioned volunteer are a very dangerous combination.
I set about making molds to press new ribs when a gentlemen visited the hangar and told me about a business in Australia that restores warbirds. I did some Internet sleuthing and tracked them down. To my amazement, they had a factory fresh set of ribs and the forms to make the wing skins! The ribs and a set of skins were shipped to me last week and we're anxiously awaiting them at the Cobra Den.
I have SEVERELY limited the personnel who can work on the plane now. Only trained, licensed mechanics will be involved. We did run it last week for a while to get it hot for an oil and coolant change change. Sure was good to hear that Allison fire up again. We are putting the finishing touches on a flap skin and will be ready to rock when the package arrives from down under!
I'll post photos of the progress.
Thanks!
Re: CAF Centex Wing P-39 News
Tue Aug 21, 2012 5:32 pm
Ray Clausen wrote:
...A little knowledge and a well intentioned volunteer are a very dangerous combination...
I have SEVERELY limited the personnel who can work on the plane now. Only trained, licensed mechanics will be involved...
Ouch. Sorry for your pain, Ray.
I would, however, encourage greater emphasis on TRAINED help rather than LICENSED. I can distinctly recall a warbird project (on which I was an unlicensed volunteer) whose decision-makers hired a couple of A&Ps to handle some skinning around the cockpit area. The reason I remember it so well is because I spent the next several weekends drilling out the A&P's...umm...results. (Yeah, it was that bad).
I treasure the tips I've learned from those who kept 'em flying in the old days (Well, other than the hand-turn-the-prop-backwards thing). Sadly most can't make it out to the hangars anymore.
