Grumman TBF and General Motors TBM Avenger

[Radish]

Sounds a great idea.
Perhaps I SHOULD have bought the Italeri (AccMin) 1/48th Avenger, just so I could Whiff it into a suitable COIN aircraft.  

[Captain Canada]

I've got a single seat Royal Canadian Marines attack type Avenger about half way done.....another that should be done this year, after the move......

 

[Jeffry Fontaine]

After taking a second and third look at the image that Leigh posted on my EW Avenger thread, I would recommend that you consider extending the existing engine cowling to accomodate another row or two of cylinders.  This is based on the fact that the Skyraider engine cowling is much longer than the cowling on the Avenger so it would need to be extened to accomodate the additional rows of cylinders of the R-3350 from the Skyraider. 

Incorporating a pair of 20mm cannon into the wings would be practical for maximizing the available destructive power for forward firing weapons.  These would occupy the original position in the wing where the .50 caliber machine guns were mounted with a useful ammunition supply of 500 rounds per gun.  I would think that this would be a realistic quantity but maybe a larger ammunition supply could be envisioned with the more powerful engine?  I would not recommend placing a gun on the fuselage over the engine since synchronization of the weapon to fire between the advancing propeller blades is something that is just waiting to go wrong.  This would also free up space in the fuselage for additional equipment and fuel.  The two 20mm cannons should be more than adequate for suppression of most targets. 

Later models of the Avenger were provided with at least one pylon for a fuel tank or radar pod in the inboard wing section between the fuselage and the wheels.  This really does not do much for effective ordnance selection as the pylon was situated in such a manner that anything too large would interfere with the bomb bay doors or the wheels so size was a limiting factor. 

The outboard sections of the wings were eventually provided with at least four stations on each wing for 3.0" FFAR (Forward Firing Aircraft Rockets) or 5.0" HVAR (High Velocity Aircraft Rockets) which were also known as "Holy Moses" (more like "Holy Sh*T!" Look at that thing go!).  The weight of the 5.0" HVAR would be in the neighborhood of a 250 pound bomb more or less so using a standard bomb pylon such as those used on the later Corsair (F4U and AU-1) or the Skyraider would work in this case to allow additional ordnance to be carried on the wings instead of rockets.  This would mean that the additional ordnance loaded under the wings would be in the neighborhood of 2000 pounds if you are calculating each bomb or rocket to weigh at least 250 pounds.  So if you are strapping a ton under the wings and a ton or more inside the bomb bay, all of a sudden you have a warload of 4000 pounds which is quite useful for air support missions. 

If you were to keep the turret option open and use the twin machine gun turret on the Avenger that DB posted in his original image, you could go retro and paint the Avenger in USAAF or RAF/RAAF/RNZAF markings and use it in a Korean war or WWII scenario providing air support to ground troops (I kind of like this idea) instead of the Consolidated Vengance, Helldiver, or Dauntless.  If you go with the USAAF attack aircraft, you could also consider using the three round 4.5"/115mm folding fin rockets that were carried by the P-47 and P-51 in those three round tubes.  While the original 4.5"/115mm rockets were not real fast, they did pack a lot of explosives and created a lot of damage.

The Aeroweb reference page on the TBF/TBM Avenger provides additional variations on the Avenger. 

The VA-145 "Swordsmen" web page which provides a little bit more information on the various production models of the Avenger as well as the conversions. 

Continuing research on the subject of a USAAF/USAF attack version of the Avenger has led me to the following results at this link from ibiblio - Open and Free Resources the public's library and digital archive It is a text file and it appears to be quite accurate in regards to the numbering and accounting for all of the various A-XX numbered attack aircraft used by the US.  It shows that the following "A-XX" numbers are candidates for assigning to the WHIF Avenger that was used by the USAAF/USAF during WWII and Korea:

A-39, A-40, A-46, A-47, A-48, A-49, A-50, A-51, A-52, A-53, A-54, A-55, & A-56

Just for clarification, the A-38 was assigned to the Beech Grizzly and the A-41 was assigned to the Vultee dive bomber. The A-57 designation was originally assigned to the Martin B-57.  Which A-XX designation would you prefer to assign to the Avenger?  I was going to do a poll but there are too many choices to be made to allow it to work.

[SinUnNombre]

After taking a second and third look at the image that Leigh posted on my EW Avenger thread, I would recommend that you consider extending the existing engine cowling to accomodate another row of cylinders...............




................While the original 4.5"/115mm rockets were not real fast, they did pack a lot of explosives and created a lot of damage.

All of the modifications you posted are pretty much what I had in mind. I agree with you on extending the cowling to fit the 3350 for better cooling. In fact, I think I just found the perfect piece to do it with in my parts box. Ironically enough, the plastic is almost the exact same color. Interesting... On the 20mikes for the wings, I was thinking of mounting Hispano 20's like in the wings of Tempests, Spits, etc. I just think they would look cool and are plausible. Those would probably be scratchbuilt. Rockets, I've got a set of 12 HVARs also from the Airfix Skyraider. Just to make sure I heard you right, you said FOUR rockets PER WING, correct? For the turret, I would definitely like it to be two gunned, but by keeping the original turret and simply adding another gun to it, I cut down on the workload for myself. I love the way the turret DB posted looks, but to use that exact turret, first I haveto find out exactly where I could get one, then buy the kit, then fit the turret to the Avenger fuse and make it look like it was meant to be there. Just trying to make it a little easier on myself, seeing as how I'm not only in the middle of moving but I'm working 75+ hour weeks, and I'd really love to actually finish a model for once. I'm not sure for the designation, but I think -39, -40, or -46 might be the best ones on that list. I'm thinknig of keeping if USAF or maybe RNZAF for Korea. What kind of camo would work for that? Big thanks to all who have contributed so far. Let's keep this going and develop the idea even more. I'll post progress as it happens in a thread over in the Dead Parrot GB.

Jon

edit: Looking at how that Martin turret is mounteed in DB's pic, it might not be that much work to monut it on this kit. But I think it will still be easier just to use the original kit turret and add a gun.

[dogsbody]

Nit-picky again. With the way the Avenger turret narrows in at the top, I wonder if there would be enough room for two gons and the gunner. If I recall correctly, the Averger gunner sat slightly off-center.

[SinUnNombre]

Nit-picky again. With the way the Avenger turret narrows in at the top, I wonder if there would be enough room for two gons and the gunner. If I recall correctly, the Averger gunner sat slightly off-center.

That kinda bugged me too. I had figured out a way that involved remounting the gun from between the mount and the seat, to the other side of the mount, then doing the same to the added gun on the other side, also narrowing the seat. But I don't think there would be enough room to cram everything in there.Ahh, screw it, it will end up being easier to just add a Martin turret, and it will probably look better too. What kind of plane can I find a Martin 250E turret in? Something there is a 1/72 scale kit of, please. ^_^  

Jon

[dogsbody]

What if you used the Grumman turret, but stacked a pair of .50's, one above the other? It would be a twin .50 mount, but still using the original turret glazing.

[SinUnNombre]

What if you used the Grumman turret, but stacked a pair of .50's, one above the other? It would be a twin .50 mount, but still using the original turret glazing.

I dunno. That would work, but the  Martin turret's definitely started to grow on me. It makes the conversion look a little more complete to me, you know what I mean? I'll sleep on it, but right now I'm leaning towards the Martin.

Jon

[Jeffry Fontaine]

What kind of plane can I find a Martin 250E turret in? Something there is a 1/72 scale kit of, please.

The twin machine gun turret looks a lot like the same turret found on the top of the B-17, B-24, B-25, and B-26.  Also the same one that was also used on the Privateer as well.  

The color scheme for the early WWII would be the same as most other USAAF aircraft; Olive Drab top and Gray undersides.  The national markings would be for that particular period and theater of operations.  

If the Avenger actually lasted long enough to be used during the Korean War, you could expect to see it in NMF.  

Regarding the rocket load out.  Yes, four RP for each wing.  Late models of the Avenger were provisioned for four rockets under each wing.  Early rocket launchers were the same rail type as used by the RAF/RN on Mosquitos, Hurricanes, Typhoons, and the Liberator.  Late war modifications changed the rail launchers out for the traditional two stub zero-length launcher for the 5.0"/127mm HVAR.

[elmayerle]

This is probably a bit off topic, but the Russians brought some old Il-28 Beagles out of mothballs for use in Afganistan as the rear turret gave the aircraft a measure of protection from Stingers etc. These were being fired from the rear arc. So if you are planning to go where they shoot back a rear gun ain't a bad idea!

Yeah, but the IL-28's rear gun position has a lot more field of fire than the turret on a TBF has.  It makes a difference, I'd imagine.

[Jeffry Fontaine]

This is probably a bit off topic, but the Russians brought some old Il-28 Beagles out of mothballs for use in Afganistan as the rear turret gave the aircraft a measure of protection from Stingers etc. These were being fired from the rear arc. So if you are planning to go where they shoot back a rear gun ain't a bad idea!

Yeah, but the IL-28's rear gun position has a lot more field of fire than the turret on a TBF has.  It makes a difference, I'd imagine.

But the Avengers had a ventral gun as well.

That ventral gun was very limited in the firing arc as well as depression and elevation.  I imagine you would have better luck in a telephone booth fire fight at hitting your target.  The ventral gun on the Avenger was more of a "pray and spray" psychological weapon for the Avenger crew.  The description given about the crewmember having to stand up and shoot downward is a position better used in front of a urinal for hitting the target.  Besides, the low level of the torpedo attack run would normally preclude anything from sneaking up underneath the aircraft unless it was a submarine.

[datguy]

[snip]I think the best route to take with this would be to create a series of RDF antennas on the fuselage and wings to allow triangulation of RADAR and radio signals for an Electronic Surveillance Aircraft. 

A second version could be created using the selective application of several tear-drop shapes to the fuselage and wing tips to create an Electronic Countermeasures support aircraft with an active jamming support mission.  [snip]

I agree that two different versions would be required for ESM and ECM.  The two missions are simultaneously incompatible -  you can't jam while surveilling.  The weight and bulk of equipment (especially for ECM) would seriously degrade performance if you wanted to squeeze both into the same airframe.  Presumably, a generous supply of basic airframes would be available, so the real costs would be in equipment and the force would be mutiplied by having the opportunity to conduct ESM and ECM simultaneously in different parts of the operational area.You might want to look at the Grumman AF-2W antennae fits for ideas as well, since they used passive ESM as well as active radar in the sub-hunting role.

I think a canopy modified for lower drag would be desirable, a la the TBM-3W or the streamlined fairing like the FAA ECM Mk.6.  To give the operators adequate lighting conditions for the equipment, a painted-out or metal canopy fairing would be ideal.

I'm looking forward to seeing how your project comes along.  I've got an Airfix 1/72 Avenger without a job right now, and I'm tempted to create a follow-on to yours with the bubble canopy I proposed earlier in the thread.

DG

[Jeffry Fontaine]

I do have a spare fairing from the Esci AEW Skyraider kit that could be used for the ECM version since it has a nice curve to it and a pair of cooling scoops towards the back of it.  This would be a good way to cover up the large open area behind the pilot and create a closed up space for the electronics to be housed inside.  The ESM version would probably fare well with that feature as well.  I have a couple of spare F6F Hellcats to cut up so I can also use the bottom portion of the Hellcat fuselage in place of the stepped rear fuselage section on the Avenger.  The reason for this would be that there was no longer a need for the gun position as the war dragged on and it cleaned up the airframe and provided a bit more space internally for the electronics and crew.  This would resemble the later ASW/AEW versions that were used after the war in some respects but still with my own interpretation of the intended mission.  

Both are still in the dream about stage and have yet to be cut up at this time.  

Feel free to run with both ideas if you want.  I plan on doing this in 1/48th scale since i have a couple of the old Monogram kits to use for this project.  I still beleive in sharing information/ideas for the purpose of allowing us all to think outside the box which is one of the reasons I like this forum.

[Damian2]

some interesting info on this thread! I'd like to build my Dead Parrtot GB AD-5 as an AEW bird myself. So I can't wait to see what the Avenger looks like!!!

[SinUnNombre]

How goes the Avenger COIN project?

Well, its hit a bit of a snag. You've probably noticed that this is the first time I've been online for a few weeks. Well, I just got through with a move, and all my model supplies are scattered to the four winds. I'm still digging through bozes trying to find everything. Plus, I have to get ahold of some Evergreen sheet styrene to scratchbuild the bomb bay, as I have gotten the doors opened. So, for a little while, the motivation is there, but the supplies aren't.

Jon