Aero Vintage B-25 News updated

[aerovin]

Updated for the first day of 2010:

http://www.aerovintage.com/b25news.htm

and the B-25 Locator page with some updated photos:

http://www.aerovintage.com/b25loc.htm

B-17 News will be updated around February 1, for those who are losing sleep over it. By staggering it to every other month, it will even out the time commitment a bit.

Preview:

Ex FAD 2503 (Dominican Air Force) B-25J, circa 1965

[Jerry O'Neill]

I believe part of the FAD 2503 (Dominican Air Force) B-25J still exists at the New England Air Museum. I was told that the gun nose we had in storage back in the 1980's was from that aircraft. It was recovered when they picked up the B-25H for the museum.
Jerry

[Ken]

The news has a shot of a B-25J at the USS Alabama park. Listed as a TB-25N, how can it still have slim carb intakes and Clayton stacks?

[aerovin]

The news has a shot of a B-25J at the USS Alabama park. Listed as a TB-25N, how can it still have slim carb intakes and Clayton stacks?

Well, that's a good question and something I did not notice. My transcription of the USAF record card shows it was modified by Hayes and redesignated as a TB-25N in October 1954. Thumbing through my various references, I see numerous B-25s supposedly modified as TB-25Ns with the old carb intake and standard B-25J cowlings. There seems to be a great variation from airplane to airplane (perhaps post-USAF mods, perhaps later Hayes airplanes had the reworked cowlings but not the earlier ones?). According to a 1956 Aviation Week article, the conversions began in August 1951 and at least 1,000 B-25s were modified to become TB-25L and TB-25Ns.

Just for grins, here is a drawing that illustrates the cover of a USAF TB-25N document dated May 1954:



With a close up of the nacelle and cowling:



Granted, the shortcomings of the drawing need to be considered. I'll bet Carl Scholl could give us some good information off the top of his head.

[Ken]

Cool photo, Scott. Can you give us a "TB-25" 101 class? Tell us what the different designations indicate. Was there a TB-25J? Is the Hayes mod synonymous with TB-25N or were they two separate programs?

Not looking for a graduate level course, but a TB-25 discussion (possibly a new thread) would be cool.

Ken

[rwdfresno]

We could look back at historical pictures of the aircraft but based on the current picture it is hard to know what modications have been made ot the aircraft since it left the USAF inventory. Secondly, I have seen some refferences including Joe Baugher that indicate that the TB-25Ns intially had the R-2600-29 engine and that only some of them had the upgraded Stomberg carbs installed and the engine re-designated -35. Conversely, I have seen and have many pictures of TB-25C/Ds in service some with and some without Strombergs as well as some with and without Clayton stacks replaced with upper half collector rings.

I'd also say that it is acurate to say that any B-25J that went through the IRAN TB-25N conversion, or other TB-25 conversion program and left the USAF inventory as a TB-25N can accurately by described as such despite the being "re-converted" back to a B-25J. Similarly to B-25J 44-29035 being converted externally to appear as a PBJ-1D, it still makes it no less a B-25J. There were many other modifcations made during the TB-25 conversion process other than the carbs and exhaust as well:

1. Removal of the Bendix turret and navigator position and placment of 2 seats against the forward bomb bay bulkhead
2. Many electrical modifications
3. AN/ARN-14 radio systems
4. Additon of auto-pilot systems
5. TB-25K E-1 radar fire control systems and modifed bomb bays and radome capped glazed nose to carry radar equipment
6. TB-25M E-5 radar fire control systems and modifed bomb bays and radome capped glased nose to carry radar equipment
7. TB-25N had the addition of R-2600-29A engines
8. 60 TB-25N had the glazed nose replaced with empty solid, formerly 8 gun nose with faired over gun ports
9. VB-25N had lowered bomb bay cielings as well as passenger windows and passenger seats installed

Ryan

The news has a shot of a B-25J at the USS Alabama park. Listed as a TB-25N, how can it still have slim carb intakes and Clayton stacks?

Well, that's a good question and something I did not notice. My transcription of the USAF record card shows it was modified by Hayes and redesignated as a TB-25N in October 1954. Thumbing through my various references, I see numerous B-25s supposedly modified as TB-25Ns with the old carb intake and standard B-25J cowlings. There seems to be a great variation from airplane to airplane (perhaps post-USAF mods, perhaps later Hayes airplanes had the reworked cowlings but not the earlier ones?). According to a 1956 Aviation Week article, the conversions began in August 1951 and at least 1,000 B-25s were modified to become TB-25L and TB-25Ns.

Just for grins, here is a drawing that illustrates the cover of a USAF TB-25N document dated May 1954:



With a close up of the nacelle and cowling:



Granted, the shortcomings of the drawing need to be considered. I'll bet Carl Scholl could give us some good information off the top of his head.

Last edited by rwdfresno on Fri Jan 01, 2010 2:33 pm, edited 1 time in total.

[aerovin]

Cool photo, Scott. Can you give us a "TB-25" 101 class? Tell us what the different designations indicate. Was there a TB-25J? Is the Hayes mod synonymous with TB-25N or were they two separate programs?

Not looking for a graduate level course, but a TB-25 discussion (possibly a new thread) would be cool.

Ken

Not an expert, but thumbnail information:

TB-25Js were standard B-25Js designated as TB-25Js when assigned as trainers and/or squadron hacks and/or other uses. B-25J was the highest production series; all after this were modifications.

TB-25Ks were B-25Js modified primarily as radar trainers by Hughes Aircraft and equipped with E1 radar fire control systems. At least 117 were modified.

TB-25Ls were B-25Js modified by Hayes Aircraft and Hughes Aircraft to "afford specialized advanced training in twin engine bombers." At least 73 were done by Hayes and 49 by Hughes.

TB-25Ms were advanced radar trainers modified by Hughes with E5 radar fire control systems. At least 40 modified.

TB-25Ns were B-25Js modified as advanced twin engine trainers. My understanding is that most of the systems: electrical, hydraulic, controls, and fuel were all replaced with new or redesigned components. No armament or provisions for bombs in the airplane. As of May 1954, 380 B-25s were slated to be modified as TB-25Ns but as I noted in my above posting, the 1956 Aviation Week article stated that 1,000 B-25s had "gone through the Hayes shop since" August 1951. Not all of those were TB-25Ns but a good number were and the mods were still going on in March 1956. A May 1954 tech order shows, by serial, 112 TB-25Ns (and 44-31004 is not on the list, but supposedly not modified until October 1954).