Pemberton Goose Update

[Dan K]

http://www.antiqueairfield.com/articles ... rton-goose

[JohnCFord]

That's a pretty nice looking man cave right there. Glad to see another Goose on the way to airworthy.

~J~

[JohnB]

I stopped by the hangar last weekend, it's really coming along. The center section back on the hull makes it look like an airplane again.
Addison is planning for flight in the summer of 2015, so there's still a lot to do.

[airnutz]

Thanks for the update...she's coming along nicely! If you go to the homepage(scroll down a little) they announced completion of this seasons flight tests of the GeeBee QED replica with a video of her landing at her winter field for mods before final flight tests this spring.

[Rajay]

Boy that Goose sure looks like it's all shiny silver - as opposed to dull gray, as it would be if there was any original Grumman's type 1 chromic acid anodized skin left on her.

Is there (any dull gray anodized original skin left on her) or has virtually all of the original skin been replaced by now, either by Addison & company or by previous restoration efforts at PSAM or before?

Last edited by Rajay on Thu Dec 05, 2013 9:51 pm, edited 1 time in total.

[JohnB]

Addison has not replaced any skin of the fuselage.

[TheBoy]

Boy that Goose sure looks like it's all shiny silver - as opposed to dull gray, as it would be if there was any original Grumman's type 1 chromic acid anodized skin left on her.

Is there (any dull gray anodized original skin left on her) or has virtually all of the original skin been replaced by now, either by Addison & company or by previous restoration efforts at PSAM or before?

Interesting note about the chromic acid Dave. Based on that assumption, there is one(!) original skin left. It is about a 12"x12" skin on the right side under the center section. Like John said, we haven't touched the fuselage skins (yet).

With that said though - I have a hard time believing that is really all that is left that is original. Our records show the nose (station 4 and forward), the hull from the step forward, and the spar in the vertical fin all being replaced but nothing else. I'd HOPE that there might be some causal mention of "reskinned entire fuselage" if that was indeed done. The skins on the lower side of the center section still retain the flat dark gray appearance which does jive with the records - we know they spars caps and upper skins were replaced.

They all have their own stories and history which is part of the fun. Based on what you've pointed out I'm going to go back and review the airplane and the records a little closer looking for any other indication that the skins may not be factory.

Ryan

[Rajay]

Here's a photo of N66QA (G-21A s/n 1054) and N641 (ex-USN JRF-5 s/n B-115) in the old Antilles Seaplanes shop in Gibsonville, NC in 2005:



See how gray N66QA looks? It has many places that have been patched and other areas where its anodization has been scoured or ground off, but essentially, it's an original hull. The tail and aft fuselage are still etched where it carried its original markings as NC3055 as the "Texaco 34" Goose - the exact same all-red Goose with a white lightning stripe that is represented by the Ertl 1/48 die-cast model marketed as a Texaco collectible in 1996 (I bought 5 on eBay for just a few dollars each - and one of the coin banks was actually full of change. I made most of my money back with that one!)

The Ertl model missed the fact that the lower hull was actually painted black from the waterline down and the green trimmed engine cowlings that Ertl used were actually not used on this Goose, but rather on a later Grumman G-73 Mallard...but I digress!

Here's a better photo of N66QA:



And here's one of the aforementioned Ertl coin banks:



On the rudder in black it said "NC3055" and on the vertical stab in white it said "The Texas Co."

The model shows the Texaco star just forward of the Sta. 29 bulkhead near the back of the aft baggage area, but in reality it was slightly farther aft and was about 90% behind the Sta. 29 bulkhead on the outside of the fuselage....

Note as well that the model shows a "Goose door" cargo or smokejumper 2-pc door on the right side where the original Emergency exit was located - but the actual "Texaco" Goose never had that particular mod. The model also shows a 1-pc modified bow hatch, but once again, the actual "Texaco" Goose did not have that mod either; it still has the original 2-pc, side-hinged bow hatches. My theory is that Ertl used Bill Rose's Goose N600ZE (s/n B-100, now owned by Bob Martin near Baltimore) for a reference. At the time the model was produced, Bill was not to far away from where Ertl is located.

[TheBoy]

So I did a little more digging/snooping on this and I found this skin.



This is immediately behind the copilot's sliding window. It's pretty clear that this skin was an original skin, treated with the chromic acid, however something along the way has stripped/buffed/scraped/whatever'd off the protective coating on half of the skin. I did find a couple of other skins reflecting this same state, where you could see they had been treated but most of the signs had been removed. I'm not sure what they could have done to remove it, let alone WHY someone wanted to.

This does support the aircraft record though that show no indications that the airplane had been completely reskinned. It really is unfortunate that somebody in the airplane's past did this as it really is a superb form of corrosion protection. I guess it's a good thing that this airplane is probably done with it's working life and moving into it's retirement

I'd be interested in any other thoughts and information you'd have on the chromic acid subject.

[Cvairwerks]

Ryan: A careful examination of the area around the rivets on the aft side of that skin and some of the ones below the angle might give youi some clues as to how it was done. Using a bright light, with a daylight color temperature ( over 5000K ) and a good 5-10X glass, look around the rivet heads and at the skin joints. If there is no evidence of the old coatings, either the skin has been removed and cleaned then reinstalled or had rivets changed out, or some high powered chemical work was done to strip it off. The alternative is that you find some indications of mechanically removing the coatings.

Either way, an interesting question in her history.

[Rajay]

... or some high powered chemical work was done to strip it off. The alternative is that you find some indications of mechanically removing the coatings.

Do you actually know of any such "high-power" chemicals that would dissolve or otherwise remove Type 1 Chromic Acid Anodize? I've never heard of any - of course, not that that means there aren't any.

Just in my own personal experience with Gooses and Anodized parts, even mechanical means of stripping them usually doesn't touch the Anodize coating. In my experience, this original type of Anodize generally resists even plastic bead, walnut shell, and baking soda blasting. Much less than harming it, I've even seen such blasting restore a kind of luster or sheen to the Anodize coating. Even harsh sand blasting has a tough time stripping it and it certainly doesn't do it cleanly.

The only other way that I have seen to get it off (not that you'd ever really want to remove it) is to literally sand it off with relatively coarse grit sandpaper - and that usually damages the underlying aluminum sheet too.

That's why I was kinda assuming that more skin had been replaced at some point than apparently was recorded in its logbooks according to Ryan. I've heard that it went through a couple of other rounds of "restoration" prior to being obtained by the Pembertons. Maybe one of those previous efforts didn't bother to record the fact in the maintenance logs 'cuz they assumed that it was for museum display only from that point on and they thought that it would never be made "airworthy" ever again. Maybe....

The most important fact at this point is that if that was the case, they were wrong!

[Cvairwerks]

Rayjay: I have heard about a process that is Boeing approved for stripping the anodize off of incorrectly done parts for some of their products. I don't have direct knowledge of the process, but I have been told about it. There is a company here in the DFW area that developed the process and the chemistry. I don't know if they are still in business or not. Their website is not up so I can't confirm.