UH-1C to UH-1F converion

[Ben Brown]

Hi all,

What would be involved in converting a Monogram UH-1C to an F? Other than the D tail boom, it looks like the only major difference is the aft end of the engine cowling, to accomodate the side exhaust. Have I missed anything? I'd like to some day do a SEA-camo'd F with the 7-shot rocket pods fitted.

Thanks!

Ben

[EDWMatt]

Hi all,

What would be involved in converting a Monogram UH-1C to an F? Other than the D tail boom, it looks like the only major difference is the aft end of the engine cowling, to accomodate the side exhaust. Have I missed anything? I'd like to some day do a SEA-camo'd F with the 7-shot rocket pods fitted.

Thanks!

Ben

You've captured most of it Ben. Major external differences are modified aft cowling for the T-58 engine (for the exhaust and the 180-deg gearbox), extended tailboom (with the baggage compartment, like on the civil 205A) and the 48-foot main rotor.

I believe the armed UH-1F's were designated UH-1P

[rotorwash]

Hi all,

What would be involved in converting a Monogram UH-1C to an F? Other than the D tail boom, it looks like the only major difference is the aft end of the engine cowling, to accomodate the side exhaust. Have I missed anything? I'd like to some day do a SEA-camo'd F with the 7-shot rocket pods fitted.

Thanks!

Ben

Ben,

The longer tail boom and the T-58 engine with the right hand exhaust are two big differences. Plus you'll need the 48 ft 205 rotor from a UH-1D/H kit as well. Also, the particle separator on the UH-1F/P was different and there are at least two different types. One is similar to that used on UH-1Bs and UH-1Cs after 1966 in Vietnam and the other is completely different so you'll want good refs of the ship you are building. There is also a luggage compartment on the right front part of the tail boom. in fact, the tail boom is actually the same as the civilian 204B instead of being a UH-1D/H tail. The Italeri D/H or even UH-1N kit tail would work as it has the baggage compartment. If you are intending to build the armed UH-1P you'll want to make two XM-93 minigun systems for the door gunner positions to go along with the rockets as that was the standard setup. I can post some pics of armed UH-1P's if you'd like. HTH

Ray

[Tank]

Ben,

The longer tail boom and the T-58 engine with the right hand exhaust are two big differences. Plus you'll need the 48 ft 205 rotor from a UH-1D/H kit as well. Also, the particle separator on the UH-1F/P was different and there are at least two different types. One is similar to that used on UH-1Bs and UH-1Cs after 1966 in Vietnam and the other is completely different so you'll want good refs of the ship you are building. There is also a luggage compartment on the right front part of the tail boom. in fact, the tail boom is actually the same as the civilian 204B instead of being a UH-1D/H tail. The Italeri D/H or even UH-1N kit tail would work as it has the baggage compartment. If you are intending to build the armed UH-1P you'll want to make two XM-93 minigun systems for the door gunner positions to go along with the rockets as that was the standard setup.

See, I told you he would know Ben. W/O pulling them out and looking does your CD cover on of them?

I can post some pics of armed UH-1P's if you'd like.

Havn't we been over this before. Yes, please post.

[rotorwash]

See, I told you he would know Ben. W/O pulling them out and looking does your CD cover on of them?

Havn't we been over this before. Yes, please post.

First off, sorry Matt, looks like we were posting at the same time. I didn't mean to be redundant.

The Rotorwash short bodied Huey DVD has photos of the first UH-1F from PIMA, a UH-1F in crash rescue colors from Werner Robbins and a UH-1P from Werner Robbins with closeups of the XM-93 gun system. Here's a few of those pics so you can see what's on the DVD. The DVD pics are much higher res, however. I'll post some Vietnam 20th SOS pics in a bit.

Ray

First UH-1F Pima:

UH-1F Werner Robbins:

UH-1P Werner Robbins. This bird is not set up exactly like most 20th SOS UH-1P's. First off, no rockets and second only 1 XM-93 system. Typically, there was one system in each door:

[thatguy96]

I believe the armed UH-1F's were designated UH-1P

The complete set of differences between the UH-1F and UH-1P is not entirely clear.

Here are the official lines from DoD 4120.15L, Model Designation of Military Aircraft, Rockets, and Guided Missiles, over the years:

1974: "Similar to UH-1F, except modified to perform additional missions under adverse conditions."

1998/2004: "Upgraded UH-1F modified to perform classified missions."

The only modification that is clear is the additional radio antenna blade on the roof. The helicopters would not have had to have been modified in any way to carry the armament. As you can see easily in the picture Ray posted of the UH-1F from Werner Robbins, the rear armament hard points were standard on the UH-1F.

The CHECO report on USAF helicopters in southeast Asia is still classified. I put in an FOIA request on it, but so far I haven't heard anything. If I ever get a copy of it, I'll be sure to share what's inside.

Edited March 14, 2010 by thatguy96

[rotorwash]

The complete set of differences between the UH-1F and UH-1P is not entirely clear.

Here are the official lines from DoD 4120.15L, Model Designation of Military Aircraft, Rockets, and Guided Missiles, over the years:

1974: "Similar to UH-1F, except modified to perform additional missions under adverse conditions."

1998/2004: "Upgraded UH-1F modified to perform classified missions."

The only modification that is clear is the additional radio antenna blade on the roof. The helicopters would not have had to have been modified in any way to carry the armament. As you can see easily in the picture Ray posted of the UH-1F from Werner Robbins, the rear armament hard points were standard on the UH-1F.

The CHECO report on USAF helicopters in southeast Asia is still classified. I put in an FOIA request on it, but so far I haven't heard anything. If I ever get a copy of it, I'll be sure to share what's inside.

The 20th SOS was basically a covert ops unit. Therefore, their helo configurations were very secretive. The UH-1P was disignated as a Psyops bird, but was actually just a UH-1F gunship. there really isn't much confusion about this except perhaps when you look at "official" literature. The additional blade antenna on the roof isn't a sign of a UH-1P as some UH-1P's only had one. Here are some pics from the 20th SOS courtesy of Stuart George that will make this point quite clearly. This is one case where photos and eye witness accounts are more reliable than the official literature.

Ray

UH-1F with single blade antenna:

UH-1P with XM157 sysytem and XM93 minigun visible in the cabin:

Wide view of a UH-1P with only one blade antenna. Of course many did have the dual blade antennas, but so did many UH-1F's.

Here's a UH-1F from the Wayne Mutza collection with two blade antennas. Notice also the different particle separator on this bird vs the Vietnam birds above:

Edited March 15, 2010 by rotorwash

[thatguy96]

Ray, out of curiousity, how are you identifying the aircraft as either UH-1F or UH-1P? Is it just from the information provided by the source? The only reason I ask, is that for instance, if that last bird is 63-13162, then information I can quickly find on the web says it was converted to a UH-1P. The 20th SOS also was initially equipped with UH-1F, and I might suggest that the second to last picture is actually a UH-1F. This would be based on the fact that the M156 universal mounts appear to have only been used very early on before being replaced with BRU-20/A bomb racks.

I don't think any of the UH-1Ps were new production. It wouldn't surprise me if the data plates in all the aircraft still said UH-1F, regardless of the configuration. I get the feeling that in the field the nomenclature was used pretty interchangeably, though some sources suggest that the slicks were generally being referred to as UH-1Fs and the gunships were referred to as UH-1Ps. I really don't know. You've talked to far more people than I have on this. I'm hoping that eventually I'll get my hands on the CHECO report.

Edited March 15, 2010 by thatguy96

[rotorwash]

Ray, out of curiousity, how are you identifying the aircraft as either UH-1F or UH-1P? Is it just from the information provided by the source? The only reason I ask, is that for instance, if that last bird is 63-13162, then information I can quickly find on the web says it was converted to a UH-1P. The 20th SOS also was initially equipped with UH-1F, and I might suggest that the second to last picture is actually a UH-1F. This would be based on the fact that the M156 universal mounts appear to have only been used very early on before being replaced with BRU-20/A bomb racks.

I don't think any of the UH-1Ps were new production. It wouldn't surprise me if the data plates in all the aircraft still said UH-1F, regardless of the configuration. I get the feeling that in the field the nomenclature was used pretty interchangeably, though some sources suggest that the slicks were generally being referred to as UH-1Fs and the gunships were referred to as UH-1Ps. I really don't know. You've talked to far more people than I have on this. I'm hoping that eventually I'll get my hands on the CHECO report.

Joe,

I call any Air Force slick with a T-58 engine a UH-1F and any AF gunship with a T-58 a UH-1P. Every credible source I can find indicates it was just semantics whether you call it an F or a P. They were all the same airframe. In fact, some authors will just say UH-1F/P as it depends on the configuration on a given day. Basically, I think it was a way to let those " in the know" tell how many gunships were being used on a mission vs slicks. I hope you get the CHECO report, but I'm betting it won't clear this one up. Cross border ops were meant to be murky. Heck, there is even a pic of a stateside "P" model being tested with psyops speakers even though there is no record of them being used in SEA. By the way, if anyone has a real interest in the green Hornets, I'd get a copy of "Green Hornets: the history of the US air Force 20th Special Operations Squadron" by Wayne Mutza. It is filled with pictures of all the 20th SOS birds as well as lots of first hand accounts.

Ray

[Ben Brown]

Somehow my "Thank you" post never stuck, yesterday. So 'Thank you" for the info and photos, guys! Now, all I need is time to build the model.

Thanks!

Ben

[Chief Snake]

Joe,

I call any Air Force slick with a T-58 engine a UH-1F and any AF gunship with a T-58 a UH-1P. Every credible source I can find indicates it was just semantics whether you call it an F or a P. They were all the same airframe. In fact, some authors will just say UH-1F/P as it depends on the configuration on a given day. Basically, I think it was a way to let those " in the know" tell how many gunships were being used on a mission vs slicks. I hope you get the CHECO report, but I'm betting it won't clear this one up. Cross border ops were meant to be murky. Heck, there is even a pic of a stateside "P" model being tested with psyops speakers even though there is no record of them being used in SEA. By the way, if anyone has a real interest in the green Hornets, I'd get a copy of "Green Hornets: the history of the US air Force 20th Special Operations Squadron" by Wayne Mutza. It is filled with pictures of all the 20th SOS birds as well as lots of first hand accounts.

Ray

On the website of the March Field Air Museum there is a very nice dialog on the UH-1F and UH-1P. This includes how many of each were bought and how they were used until they were replaced by UH-1N helicopters. Museum information is generally pretty good for all around descriptions and use. Anything done secretly may or may not be disclosed.

Chris M

aka Chief Snake

[salvador001]

I have a question, can the UH-1F be fitted with an ASE upward exhaust dust? noticing that the exhaust is in the side...

Rod.

[rotorwash]

I have a question, can the UH-1F be fitted with an ASE upward exhaust dust? noticing that the exhaust is in the side...

Rod.

Rod,

I'm assuming you mean the "toilet bowl" exhaust to cool the exhaust by forcing it upward into the rotor. I have never seen that on a UH-1F and the UH-1F was basically out of front line service before the anti-strella mod was introduced. As to whether it COULD be done, that's a different story. I'm really not sure.

Ray

[salvador001]

Ok , thanks Ray, by the way when was the anti -strella kit introduced?

Rod.

[rotorwash]

Ok , thanks Ray, by the way when was the anti -strella kit introduced?

Rod.

Rod,

I'm not sure of the exact date. Chris (Chief Snake) might have a better idea. However, the anti-strella kit was certainly being used by the time of the Easter Ofensive in 1972. The two XM26 equipped TOW Hueys which participated in the Offensive both carried the anti-strella mod at some point. However, I believe both came in-country without the kits installed. Also, AH-1G cobras were fitted with it at this time as well. I have only seen a few Vietnam UH-1H's with the anti-strella kit and they were all 1972 birds as well. I would guess late 71 to early 72 as the introduction date for the kit. While the 20th SOS still flew UH-1F/P's at that time, they were being phased out in favor of the UH-1N. HTH

Ray

[salvador001]

Thats good information Ray, here in El Salvador was very efficient that equippment, when we received our first batch of hueys in 81, they didnt came with any modification,they even looked like D models with the pitot tube in the nose,but they all were H.. but later on our air force officials with U.S. Army advisors came with the idea that all of the Hueys that will come in the near future have to come with the anti-strella kit installed and all the components that require, that was because the communist guerrillas had introduced the SA-7b, SA-14, SA-16 and Redeye, they mostly came from Nicaragua and arms runners in the middle east. I have a photo somewhere of a UH-1H of the U.S. Army based in Soto Cano Palmerola flying in El Salvador in the late 80s with all the anti-strella kit and fitted with an ALQ-144 and a UHF antenna in the tail boom, some of our Hueys were later eqquiped with that system and a FLIR for night missions.

I remember a confession of a Huey pilot that in a mission after dropping the special forces, the Huey formation composed of 15 helos climbing to an altitude of 10,000ft for a ``zona segura de retorno´´(a secure zone for returning to base), a ``boina verde´´ (green cap) officer of the U.S. Army was in the huey confirming the missile threat with binoculars, that minutes later an O-2/B working as a FAC advised them to be careful beacuse they saw some guerrillas climbing a hill with SAMs in their shoulders. When they were reaching 4,500ft they saw a chem trail of a SA-7 fired and coming directly to their huey(it was the last in the formation), that huey unfortunately didnt have the ALQ-144, only the basic anti-strella, one of the huey gunners had a flare gun and shot 3 rounds, thank god the missile hit one flare and in sort of seconds an A-37B Dragonfly came to``limpiar el area´´(clean the area) and dropped some MK82s and the threat was eliminated...

We sadly had some Aircraft shot down with SAMs, including an AC-47, an A-37B, an UH-1M i think.

If you want to know other combat Huey stories just let me know, i know a lot and very interesting, even the shot down of a U.S. Army UH-1H by artillery fire.

Thanks and greetings.

Rod.

Edited March 16, 2010 by salvador001

[Drifterdon]

I know this is reviving a really old thread but I'm trying to see if anyone has done a resin conversion for the UH-1F/P in 1/48. I've seen a couple nice build ups but nothing on how they did the sreened in areas on the port side of the aft engine area, opposite the exhaust.

Don

[Ben Brown]

Here's how Don Fogal did his:

http://www.network54.com/Forum/47751/message/1389640574

http://www.network54.com/Forum/47751/message/1389735098

http://www.network54.com/Forum/47751/message/1389831893

http://www.network54.com/Forum/47751/message/1390427754

http://www.network54.com/Forum/47751/message/1390578833

He used photo etched screen. I'm still not sure how I'm going to go about lengthening the tail boom. That has me bugged more than the engine cowling. This might be a good conversion for Cobra Company.

Ben

[Tank]

I like how you are thinking on this Ben but a resin tail sounds like an issue, super tail heavy and no place for weight up front or are you talking about the engine?

What I am missing is, if you where already hacking up a D tail boom why not use the whole thing?

Edited July 30, 2015 by Tank

[Ben Brown]

You're right, I'd might as well hack up a D kit, since I'm going to rob the rotor assembly from it, anyway. I actually had the Monogram B/C and Italeri D/H kits out yesterday to have another look (instead of working, just like I should be working right now... ). I'm thinking it might be easier to just lop the Monogram boom off somewhere aft of where it plugs into the fuselage and graft the D boom on at that point. The two booms match up pretty well, so you wouldn't have to do a lot of sanding and filling. I don't see a way to plug the D boom directly into the Monogram fuselage, because of the way the boom fairs into the fuselage is too different between the two types. If you put a splice in, you'll have to worry about the decreasing size of the boom as it goes aft, so you might end up with a step at the splice.

The engine cowling would be relatively easy. I was thinking of just vacuforming the rounded section at the aft end.

I mentioned somebody should do this in resin because I'm lazy and think it would be great if somebody else did all of the hard stuff. :D I don't think you could fit enough weight in the nose to balance a resin boom.

Ben

[Chief Snake]

You're right, I'd might as well hack up a D kit, since I'm going to rob the rotor assembly from it, anyway. I actually had the Monogram B/C and Italeri D/H kits out yesterday to have another look (instead of working, just like I should be working right now... :whistle:/>/> ). I'm thinking it might be easier to just lop the Monogram boom off somewhere aft of where it plugs into the fuselage and graft the D boom on at that point. The two booms match up pretty well, so you wouldn't have to do a lot of sanding and filling. I don't see a way to plug the D boom directly into the Monogram fuselage, because of the way the boom fairs into the fuselage is too different between the two types. If you put a splice in, you'll have to worry about the decreasing size of the boom as it goes aft, so you might end up with a step at the splice.

The engine cowling would be relatively easy. I was thinking of just vacuforming the rounded section at the aft end.

I mentioned somebody should do this in resin because I'm lazy and think it would be great if somebody else did all of the hard stuff. :D/>/> I don't think you could fit enough weight in the nose to balance a resin boom.

Ben

I nominate Kitty Hawk for this project. Very worthy and much needed. I don't even have the Monogram kit to see how blending an Italeri or ESCI boom could be accomplished. Right now I am eyeballs deep with a different project but I'll keep this in mind.

Chris M

And before anyone says something, NO I do not have any contact with nor do I provide Kitty Hawk with any input.

Edited July 30, 2015 by Chief Snake

[JEFlint]

Going back to the "Is it an F or P model" discussion.

Back in 1984, Langley AFB had "P" models. I asked my dad (who was USAF Air Rescue Flight Engineer on helicopters for 24 years) what the diff was between the two, since they looked like "F" models to me. He said that the electrics for using the guns are really the only difference.

Either way, a 1/48 F/P model would be cool.

[rotorwash]

Going back to the "Is it an F or P model" discussion.

Back in 1984, Langley AFB had "P" models. I asked my dad (who was USAF Air Rescue Flight Engineer on helicopters for 24 years) what the diff was between the two, since they looked like "F" models to me. He said that the electrics for using the guns are really the only difference.

Either way, a 1/48 F/P model would be cool.

According to the 20th SOS crewmen I have spoken to, the UH-1P can be recognized by the twin blade antennas on the roof, whereas the UH-1F only had one. According to them both F's and P's can be either slicks or guns. This is totally different from my original understanding of the differences, but they said the F's were modded to Ps.

Ray

This is a P model gunship from James Green:

This is a P model slick with a ladder tied to the fuselage from James Green.

Here is a F model gunship and an F model slick from Don Joyce. Notice the single blade antenna:

[Ben Brown]

Hi All,

Regarding the F vs P designation, I was reading through Wayne Mutza's "Green Hornets" this weekend, and it says Fs were fitted with special KY-28 radios, to prevent enemy eavesdropping, armored pilots' seats, and self-sealing fuel tanks, and these mods were extensive enough to warrant redesignating them P. He says most 20th SOS Fs were eventually upgraded to P standards.

On a conversion note, does anyone sell a XM93 minigun set-up in 1/48?

Thanks!

Ben

[Tank]

My understanding is there no aftermarket set but that the Heller UH-1N kits have some. That means the Italeri kit also has them. If that is correct, I can give you a set of mine.