Airframe Identification?

[Mustanger55]

Need some identification help from the Harvard experts here. Sorry this is a bit long winded.

The T-6 I'm doing a static restoration on is identified by the NMUSAF as an AT-6B, and there are data plates in the plane that show the serial number that supports their records. However, there are a number of anomalies that just don't add up. My theory contains some reasonable assumptions, but I don't have enough solid information to reach a definite conclusion. This airframe was "acquired" from a civilian owner for use as a display on the grounds of Chanute Air Force Base back in 1985.

This "AT-6B" has some peculiarities.
First, the tail section appears to be from a Harvard, as it has the slot window on the top of the fuselage just forward of the vertical stab, and has a rectangular baggage compartment door. It also has the cut-out for a nav light on the top spine of the fuse.
The second indicator is the cockpit finishing strips. They appear to be mostly identical to the finishing strips shown in RCAF EO-05-55A-1 Pilots Operating Instructions and identified as Harvard Mk IV. They are completely different than those shown in the engineering drawings for SNJ/AT-6 models that I've found. The difference from Mk II and MK IIA right side strips are small angle brackets that appear to hold light bulbs to illuminate the radio control panels in both the front and rear cockpits in the Mk IV.

The instrument panels and two electrical panels are definitely AT-6D, and the Radio Call tag on the front panel has the number 80705. Of course I have no proof these were original to the airframe.

Putting together these facts, and after a little online research, I think this airframe might be a Harvard Mk III. I found this quote from a New Zealand Harvard site.
"In October 1943, the first of the RNZAF's new Mk III Harvards arrived. These all metal aircraft had a different electrical system from the Mk II, being 24 volt. They also had the US style cockpit layout as opposed to the British style Mk II that had been supplied under the Empire Air Training Scheme (or also known as the Commonwealth Air Training Plan)."
From what I can determine it appears the Harvard MkIII production coincided with AT-6D production.

The missing link for me are those cockpit finishing strips. If the Mk III contained British radio equipment, and, had finishing strips basically identical to the later Harvard Mk IV, then it would seem to be strong evidence that we have a MkIII airframe here.

I know I'm drawing a lot of conclusions on circumstantial evidence, but the pieces of the puzzle I have seem to fit my theory. I'm hoping there are some MkIII owners/experts that can help me verify my conclusions.

Here are the pics of the right side finishing strips I mentioned.

[C.6-60]

Hello Norm,
I would agree with your assumptions as to the Tailcone and the interior side panels being Harvard.

As this was donated to the museum from a civilian owner anything is possible.

I have been looking over your pictures and have not been able to find a good clear shot of the Overturn Pylon on the Front Fuselage Truss Assembly.
I'm enclosing a picture of what an AT-6B Truss assembly should look like with the Gunners Seat Brace Tubes and Socket.

Please note that the Overturn Pylon tubes form a letter "N" and not an "X" which would be found on a Harvard frame.



Just as an aside Canadian Car and Foundry built Harvards can only be licensed in the "Experimental Category" by the FAA here in the U.S., North American built T-6's are licensed in the "Standard Category" and can be used for hire ( such as Flight Training, Experience Flights, Etc.)

I hope this helps,
Vincent

[51fixer]

If you can find part numbers on the parts you question and then it will help fill in the blanks.
Probably built up from parts sitting around. Harvard Tailcone with some other model parts or maybe and entire fwd fuselage from another model.
The NASM has a parts book for the AT-6B that has every part designed to be on a B when it was built. I have the section for an AT-6A/SNJ-3.
You would have to track down an equivalent for the Harvard versions as I used one many years ago. No diagrams but a listing by section of each part used.
Is there any ID plate attached to the rear fuselage tubing at the rear on the R/H side of the rear cockpit?
Is there a battery tray located on the firewall? 12V was long side to side and narrow front to rear. A rectangle.
24V was a square box, narrower but extending forward further.
Some A/C were changed from 12 to 24 at some time post war.
Good luck with your search.

[Mustanger55]

Thanks for the pointers guys,
I did a quick look through my photos and found the truss on our plane has the "N" configuration. So, this would indicate that at least the frame is T-6, right?

I could kick myself for not taking photos beneath the seats or of the forward frame when I removed the instrument panels, and I can't recall seeing the nose gun support or the gunner's seat tube brace. Another notable detail is the rearmost canopy assembly which has single side window panels. On a modeling site I followed a link to, it showed a Harvard rear canopy is longer and has two flat window panes on each side while the T-6 has single panes like the one on our plane.

This is the hard part of figuring this out. I've read other sources that describe a Harvard Mk III as simply a factory AT-6D, or, as a Harvard with a "US style cockpit layout". I would think it possible that IF the Mk III used an AT-6D tube frame, instruments and electrical panels, it might still be equipped with the Harvard tail and fuselage skins and finishing strips, especially if it retained British style radio equipment.

I'll have to look for that ID plate on the RH rear cockpit tubing. Didn't know there might be one there. The firewall isn't much help as it was stripped bare save for a few placards, so no battery tray or anything else for that matter.

I'm thinking I need to crawl through the cockpit and try to find as many part numbers as I can and search them up in the SNJ drawing index and the few parts catalogs I have. Even then, as you point out, there could be any number of variations with individual parts or entire assemblies cobbled together to make this airframe.

All this is a little frustrating because of all of the missing information. My RCAF parts catalog only lists Harvard 2, 2A & 4, skipping over the Mk III. The AN 01-60F-2 E&M that came with the SNJ Drawings covers AT-6, AT-6A,B,C,D SNJ3,4,5 Harvard IIA & III, but only shows illustrations for "Later Models" without specifying the model shown.

What I guess I need at this point is Harvard Mk III specific manuals (E&M, Pilot's Operating Inst. and Parts Catalog) and some verified original vintage photos of some Mk III cockpits. I'll have to search for those. An inquiry to Boeing's Historical Department may be in order. Their curator was very helpful on our P-51H project.

Will dig a little deeper this weekend and report any new revelations. (I'm having fun now, right? )

[51fixer]

T-6G had the single pane side glass in the canopies.
Top was 2 pieces on the top curved section with a bar in the middle.
Harvard mkIV has a single top curved piece without the center bar in the middle.

I have some extra canopy frames that would be right for the early A/C.

[bdk]

Norm,

I'm convinced you have a Harvard style tailcone.

If you look below the rear canopy you will see two parallel skin joints oriented (roughly) horizontally. One where the rear canopy assembly screws to the tailcone and one just below where the longeron is. A T6/SNJ canopy normally screws directly to the longeron whereas the Harvard canopy has that filler piece about 8" high between the canopy and the upper longeron. The Harvard filler is permanently riveted to the longeron. That filler piece has a stiffening lip bent into it at the top and one or two little triangular stiffening ribs on each side that are riveted to the deck that spans between the longerons.

It looks to me like you have a standard T6/SNJ rear canopy assembly that has been cut down to adapt it to the Harvard tailcone. My project was similarly modified at some point but the details were a bit different.



The T6/SNJ rear canopy is shorter (by maybe 12"?), so if you do have a Harvard tailcone there should be an obvious filler added to the back of the canopy.

[51fixer]

Norm,

I'm convinced you have a Harvard style tailcone.

If you look below the rear canopy you will see two parallel skin joints oriented (roughly) horizontally. One where the rear canopy assembly screws to the tailcone and one just below where the longeron is. A T6/SNJ canopy normally screws directly to the longeron whereas the Harvard canopy has that filler piece about 8" high between the canopy and the upper longeron. The Harvard filler is permanently riveted to the longeron. That filler piece has a stiffening lip bent into it at the top and one or two little triangular stiffening ribs on each side that are riveted to the deck that spans between the longerons.

It looks to me like you have a standard T6/SNJ rear canopy assembly that has been cut down to adapt it to the Harvard tailcone. My project was similarly modified at some point but the details were a bit different.



The T6/SNJ rear canopy is shorter (by maybe 12"?), so if you do have a Harvard tailcone there should be an obvious filler added to the back of the canopy.

R/H side panel is either mkIV or T-6G due to the removable square panel in the middle.

[Mustanger55]

Hey Everybody!

Got into the plane today bent on checking out all of the leads you guys provided. Turns out, the answer was right in plain sight. The tube frame has no gun support in front and no swivel seat truss in back. And, there is a filler piece aft of the rear canopy adapting it to the Harvard tail cone.
But, I did find the "Rosetta Stone" in the form of a Data Tag on the right rear corner of the tube steel frame. On it, I believe, is the true identity of this airframe.
Drum roll please...... It's a Harvard Mk IV!!!!
Data Plate reads:

Part No.
45-31105
Serial No.
4-138
INSPECTORS
CCF RCAF
86 970
DATE
9-7-52

I'm assuming CCF is Canadian Car & Foundry Co. and RCAF is, well, the RCAF. Serial number seems plain enough.

In Warbird Tech Vol. 11 it states that 270 Harvard IVs were produced for the RCAF by Canadian Car & Foundry Co., Serial Nos. CCF4-1 through CCF4-270. They were produced starting in 1952 along side 285 Harvard IVs built for the USAF and delivered under the US MDAP (Mutual Defense Assistance Program).
While waiting on their new Mk IVs, the RCAF "borrowed" 100 T-6s from the USAF. Six of these airframes were lost to accidents, and when the T-6s were returned to the USAF, six of the new Harvard IVs were substituted for the lost T-6s.

I don't have any information on the service history of CCF4-138 as of yet, but it seems plain that we have a 1952 vintage Harvard IV. How it came to have AT-6D instrument and electrical panels is still an unanswered question.

Thanks for all of the insight and help!!!!

[bdk]

Does it have fuel bladders in the outer wing panels?

[51fixer]

Just outside of the wing attach cover of both sides near the flap on the bottom of the wing would be a 2" or so round port recessed upwards an inch or so. There would be a small fuel drain port if it was a mkIV wing. Also the fuel level gauges if they are installed would be marked with a capacity of 70 gal instead of 55 gal.
The fuel selector would be marked with just Left and Right rather than R and L with a reserve position.
That is if any of these parts are installed.

[rcaf_100]

Hey Everybody!

Got into the plane today bent on checking out all of the leads you guys provided. Turns out, the answer was right in plain sight. The tube frame has no gun support in front and no swivel seat truss in back. And, there is a filler piece aft of the rear canopy adapting it to the Harvard tail cone.
But, I did find the "Rosetta Stone" in the form of a Data Tag on the right rear corner of the tube steel frame. On it, I believe, is the true identity of this airframe.
Drum roll please...... It's a Harvard Mk IV!!!!
Data Plate reads:

Part No.
45-31105
Serial No.
4-138
INSPECTORS
CCF RCAF
86 970
DATE
9-7-52

I'm assuming CCF is Canadian Car & Foundry Co. and RCAF is, well, the RCAF. Serial number seems plain enough.

In Warbird Tech Vol. 11 it states that 270 Harvard IVs were produced for the RCAF by Canadian Car & Foundry Co., Serial Nos. CCF4-1 through CCF4-270. They were produced starting in 1952 along side 285 Harvard IVs built for the USAF and delivered under the US MDAP (Mutual Defense Assistance Program).
While waiting on their new Mk IVs, the RCAF "borrowed" 100 T-6s from the USAF. Six of these airframes were lost to accidents, and when the T-6s were returned to the USAF, six of the new Harvard IVs were substituted for the lost T-6s.

I don't have any information on the service history of CCF4-138 as of yet, but it seems plain that we have a 1952 vintage Harvard IV. How it came to have AT-6D instrument and electrical panels is still an unanswered question.

Thanks for all of the insight and help!!!!

Umm, I wouldn't be making a huge announcement yet.

CCF4-138 translates to RCAF 20347, which was brought on RCAF Strength July 22, 1952.
She served at 3 Flying Training School (FTS), Claresholm, Alberta and No 4 FTS Penhold, Alberta.
Sometime in early August 1959, she was involved in an accident and was struck off RCAF Strength on August 12.

This photo from our Archives was taken on August 15th, and shows Harvards 20437, '311 and '349 stored on the ramp at Penhold following accidents. (the 'OJ' code was for No 4 FTS) By the damage, I'm guessing messy ground loop, but I don't have the accident records to know for sure.

Since '347 looks mainly intact, I imagine she was reduced to spares after being struck off.
No idea how the tubular ended up on your aircraft, but I doubt the entire aircraft is Harvard Mk 4 as the tailcone is definitely Mk II.
The Mk 4 never had the ballast weight feature, and to my knowledge the Mk III (which was never used by the RCAF) didn't have it either.

Perhaps your aircraft was originally an AT-6, and was damaged somehow in the mid to late sixties. With the RCAF retiring their last Mk 4's in 1965, a lot of surplus parts must have come onto the market, and it was probably much cheaper and easier to swap out ex-Harvard parts instead of repairing the original components. Just an idea anyways.

Sorry if this info puts you back a few steps, but at least you know the history of part of your airframe....

[rcaf_100]

R/H side panel is either mkIV or T-6G due to the removable square panel in the middle.

Wouldn't be Harvard Mk 4...CC&F never put this panel on at the factory.
Some may have had T-6G panels fitted at a later date (especially the examples that went to European air forces through the MDAP), but no RCAF Harvards had this panel on the right side.

[rcaf_100]

Does it have fuel bladders in the outer wing panels?

Just outside of the wing attach cover of both sides near the flap on the bottom of the wing would be a 2" or so round port recessed upwards an inch or so. There would be a small fuel drain port if it was a mkIV wing. Also the fuel level gauges if they are installed would be marked with a capacity of 70 gal instead of 55 gal.
The fuel selector would be marked with just Left and Right rather than R and L with a reserve position.
That is if any of these parts are installed.

As a point of interest, not ALL Mk 4's had the Aux bladder tanks installed. A lot of the early Mk 4's were built up from wartime Mk IIB spares CC&F acquired from Noorduyn.
The most visible example is the use of Mk II canopies with the extra framing on the first 120ish built, having the standard Mk 4 canopies installed at a later date.
Two of CHAA's Mk 4's (20242 and 20304) have Mk II-style fuel systems with no aux tanks and a single 'Low Fuel Pressure' warning light instead of the 'Low Fuel Quantity' warning lights for each side.
However, since our 20321 has the later style fuel system, and we are talking about this possibly being 20347, the point is moot.

On another point, it should be noted that the official RCAF designation was the Harvard Mk 4, not 'Mk IV'.
The RAF and RCAF changed from roman numerals to arabic numbering around 1950 (the Mk II became the Mk 2, etc).
However, someone at CC&F didn't get the memo as the data plates show 'Harvard Mk IV', as well as some early checklists.

[bdk]

Any photos of RCAF 20302 CCF4-93 turn up yet?

P.S. No fuel bladders in that one!

[rcaf_100]

Any photos of RCAF 20302 CCF4-93 turn up yet?

P.S. No fuel bladders in that one!

Sorry Brandon, no luck yet! I've got 20300, 20301, 20303 and 20304 but not 20302. And if Ollie's reading, no 20352 either...