Warbird Information Exchange

Sure looks like a late stabilizer from what I can tell in your pictures. How did you determine it was an early one?

Glenn,
Thanks for your input.
My reference was this P-51D in the late and early callouts.
From what I know there was the P-51 horizontal used basically from the A to the earliest D.
Early in the P-51 D use they made a change and the horizontal design was modified to a -100. This is what I am working on.
Then there was a further design change and that was the -200.
Thru my tunnel vision I referred to the -100 as early and the -200 as late.
Do I need to be educated further?
Thanks for your input.
Rich

Hello Rich,

Looks like you're having fun!

As I mentioned, it is a littgle difficult to see from your pictures so please excuse me if I am incorrect, but it appears to have the later style reinfoeced outer ribs, (spot welded doublers) Hy-Shear rivets in the elevator attach fittings, the short front feet, and the doubler on the front spar. The reason I asked is that I was just in a shop where they were modifying a late stabilizer "backwards" by installing doublers to the ribs and replacing the Hi-Shears with AD rivets per the T.O. for the early stabilizer. Some people also get tricked by the 73- forged in part number on the rear feet when what they did was use the same forgings for the late feet and then very faintly stamped the 122- number in them with number stamps so they appera to be 73- feet ad first inspection. If you really are removing the late stabilizer from the airplane and installing the early one, don't forget to modify the vertical stabilizer "backwards" to match it.

The other way to tell is to fly it! Early stabilizers seem to fly with the elev trim about 0° and late ones need about 4°-5° nose down at cruise due to the incidence change.

Nice Monarch!

Glenn,
This does have the beefier outboard ribs but the mounts are early style.
The fronts are stamped 73-21031.
The horizontal I am rebuilding was installed along with the current vertical prior to the restoration.
Rich

How far do the front feet protrude from the lower skin?

The aft edge is approx .875 below the skin.
I believe the later w/incidence change was around .500 at that same point IIRC.
Measured parallel to the aft edge of the fitting from the mounting flat to skin mounted to the rib.
Rich

Yes, the late style were shorter in the front and taller in the rear. That's why I was curious about needing to modify the vertical fin to match that stabilizer when it is installed. Assuming that you are using the vertical fin that is already installed on the tail cone.

Thanks Rich!

All the same as previously installed.
I hope all will bolt back together.
Rich

Rich,

That's why I'm a little curious. There is an angular difference and a height difference in the front foot between early and late vertical fins. The front foot on the vertical is different when used with the late horizontal due to the different angle of incidence and the rear feet of the horizontal being taller. Things get a little bound up when mismatched.

Glenn

Rich, Thanks for starting this thread.

Lots of good Mustang airframe info. here (for us beginners)

_________________
"They can teach MONKEYS to fly better than that"

http://www.heritageflight.org
http://www.bravo369.org

Wow! Did you have lessons or just sleep at a Holiday Inn Express last night? (Oshkosh this year?)

For us old time fabricators who love warbirds, this is cool sh&t! Sorry for evesdropping on a tech conversation but you guys are good!

_________________
"There are old pilots and bold pilots but few old, bold pilots."

Latest Photo of some of the cleaned up parts.
Spars and stringers have been glass bead blasted. The long upper extrusion angle will need to be replaced. The lower stringers are formed angles from sheet and cleaned up ok.
I have a few ribs to finish up cleaning and inspecting.
I had to add HVAC 6" x 8' flex conduit to either side of the 3' x 4' cabinet to be able clean the longer pieces. Even then to do the stringers which are 12' long I added a nipple used to bottle feed a calf to the end of the flex tube. This allowed me to insert the angle from the outside.
Although I think it should actually be warning Will Robinson of space intruders. "Danger Will Robinson". Now I am dating myself.

Rich

Rich,
Sorry not to get in touch with you...got your last message on the cell, but your number came up unlisted/unknown.

Please call again, or email me at onetimehilton@aol.com
Thanks, and enjoy your posts!
Gary Hilton

Rich

again, super interesting stuff, thanks for posting the progress.

Another question, if you don't mind: besides the stripping down and visual inspection of the parts that are going to be reused, how & when do you know when to do further NDT like magnafluxing (or its avaition equivalent), x-raying etc.?

Just curious...

cheers!

greg v.

Folks,
We have been working on a number of areas of the Mustang.
I have been fitting the new Odegaard Engine mount- We are fitting the new parts with the other new parts along with many original parts. It is kind like making something from connex, legos and lincoln logs. If you work at it long enough you can get it to fit.








The wings are done in Cal and our own Gary Hilton will be picking them up soon along with a couple of overhauled Merlins. Then its engine hanging time.
Rich