Other Unusual Vietnam Helicopters. (No Hueys Allowed)

Modeling Subjects Helicopters
41

Guys,

Here are some photos of a pretty rare and impressive verison of the Loach used by the CIA on a 1972 Vinh wire tap mission (project Main Street) in North Vietnam!!! Initial version of this helo (NOH-6A) was built by the Hughes under Army/ARPA programme and was named ‘‘the Quiet One’’. In fact it was so silent that it could not be heard when passing overhead at 300ft under normall ambient background sounds!!! The Army stopped there, but the project cought the eye of the CIA, who wanted to place wire taps on North Vietnamese communication lines. So the Hughes built an improved version designated NOH-6P/Hughes 500P and boy was it something else!!!

The heart of reducing the sound signature of the loach was a new 5-bladed main rotor with titanium hub and blades with 8-inch trapezoidally shaped tips that reduced tip vortexing (and by that the sound signature). Also a more powerfull -20 Allison enigine was installed with water/ethanol injection system that boosted engine power for take-offs. Tail rotor was replaced with a 4-bladed staggered mounting unit and 3.5-inches longer blades and was also mounted more to the rear to compensate for longer blades (some sources claims that main rotor blades were also longer, but I am not 100% sure of that). Engine and transmission compartments were fitted with sound-proofing material, engine intake was shrouded to further reduce trasmission/engine whine, exhaust was fitted with a resonator to lower the roar of the engine, … All the gears and transmission elements were smoothened to eliminate ‘‘grinding’’ noises. The extra main rotor blade allowed the bird to operate at 66% normal rotor rpm (an important contributing factor to reducing noise levels).

Now, if You think this is pretty impressive, wait to hear for the electronic/avionics package description…

LORAN C and INS navigation systems were fitted inside two aerodynamic pods mounted on both sides of the chopper. OH-6Ps were equiped with Radar altimeter and Radar Warning Receivers. AN/AAQ-5 FLIR with two liquid nitrogen coolant bottles was installed under the chin. Some Infra-red spot lights were fixed to skids and fuselage of the Quiet ones to enhance performance of SU-50 NVGs worn by the pilot :slight_smile: Of course, radical modifications to the cockpit were also done (still trying to find cockpit shots).

Not only were these birds able to take-off with all this load and two pilots, but they also carried two Lao commandos, who would place the wire taps!!!

The original Army/ARPA NOH-6A:

Close-up of the NOH-6A main rotor hub:

Close-up of the tail rotor (note the extended tail skid, which was neccessary to compensate for longer tail rotor blades):

A colour image of a CIA operated Hughes 500P in late 1972 at PS-77 (Laos):

Head-on shot of a CIA operated Hughes 500P (note the AN/AAQ-5 FLIR turret under the nose and how much smaller it was when compared to AN/AAQ-5 on UH-1M or AH-1G SMASH):

Here are some Taiwanese AF (RoCAF) officials examining the Hughes 500P cockpit (it was initially planned to have RoCAF pilots flying the 500Ps on the actual mission, but US pilots did in the end):

The last shot of a NOH-6P was taken in early 1990s, but it is the only I could find that shows the FLIR turret (at least I think this is the original AN/AAQ-5 turret) and main rotor tips in some detail (the larger nose mounted FLIR turret was a later addition; not used in 1972):

Enjoy the images guys,

Marko

42

Marko,

What can I say?! [bow]
Ray

43

Skypirate1, the bomb says Excedrin Headache 10,000 and then some symbol after it for pound I believe. Pretty funny actually. Just like some of the slogans on the bottom of our bombers over in Iraq, but they are not appropriate for posting on this forum.

Michael

44

In keeping with the unusuals thread and my current interest in the H-2, I’ll put forth these pics that popped up on ARC. This is UH-2A 149761 from HC-7 in Vietnam 1967. You can also find pics of it in Squadron’s “Bent and Battered Rotors: Vol 3” after it had been badly shot up off the coast of North Vietnam. Apparently, she survived the war, was converted to an F model and is currently at AMARC.

45

Jon,

It seems that this UH-2A went through a lot of camouflage changes-in that B&W shot it appears to sport a SEA style camouflage-pretty rare for Navy birds! Are You sure those ‘‘desert’’ camouflage pics are from Vietnam era?

By the way Jon, how are those AH-1G SMASH cockpit images coming up? No pressure, I just hope You didn’t forget :slight_smile:

And another thing: I posted this in the unusual Hueys thread, but it applies to this thread as well (I would really appreciate any input on this system):

I came across a very interresting piece of information while reading the 162nd AHC history: under 1968 part of the history You can find the following paragraph (direct copy/paste):

‘‘In the October-November period the 162nd was chosen to experiment with helmet sights for the XM-21 Minigun system. Sperry Rand sent a technician over to work with the Copperheads on the test of what was called the Viper Sight, or “the Look of Death”. SP5 John Ohmer (armorer) and WO Dennis O’Brien helped install and test the system which electrically/mechanically linked the pilots’ helmets to both miniguns and the M-5 grenade launcher. Wherever the pilot looked, the miniguns would be automatically aimed. It worked well under ideal conditions but the dust, heat and humidity played havoc with the small servos attached to the helmet. The system wasn’t quite ready for field conditions. This was the forerunner of the helmet-mounted sight used in the current day Apache gunship.’’

Here’s the link to the pdf:

http://www.vhpamuseum.org/companies/162ahc/162ndHistory.pdf

Now, I did some research, but couldn’t find much additional info on this Helmet sight system except that it was supposedly also tested on AH-1Gs (some sort of helmet sight system was also offered as a part of avionics package for Bell 309 King Cobra in 1971). I guess this ‘‘Viper Sight’’ was a prototype version of the later M128/M136 Helmet sight system that was used on post-Vietnam Army and USMC Cobras.

Jon, did You come across any info regarding helmet mounted sights on AH-1Gs in Vietnam, while doing research for Your AH-1 units in Vietnam book?

Marko

46

Marko,

Unquestionably those UH-2 shots are pre-1968. That particular bird was remanufactured as an HH-1D and then an SH-2F. I’m not sure if the two-tone desert scheme was stateside or not, but it is definitely a very early shot.

As for helmet mounted sights, there was a lot of experimentation going on at that point. Remember, the Cheyenne program was in full swing and it incorporated an HMS. I wouldn’t be surprised if some test articles made it to Vietnam for “proof of concept” trials.

I’ll see what I can do about getting the cockpit pics together for you. The new job has me running in circles like mad. I did get into the photo archives today though. Some really good stuff. Found a UH-1D with a really broad chord tail on it. That was kinda odd!

Jon

47

Jon,

Don’t tempt me with tails of wide chord D models, post the pics, man! Seriously, glad to see the job is going well.

Ray

48

Marcko,

Great Photos! Here is a current photo of the CIA Loach that was used in operation “Phone-Tap” still in service with the Snohomish County Sheriffs Office flown by ret. Army Pilot Bill Quistorf. It has modern versions of the FLIR & Night Sun, etc…

Tail# 66-17825

Bob

49

Alot of surplus aircraft were sold to law enforcement agencies in the early 70’s at dirt cheap prices. Glad to see some still flying

50

Cobra Fans,

I think this is an unusual Cobra, but I admit I haven’t seen as many Cobra’s as I have Hueys. I hasitate to say for certain, given my recent history with missile IDs, but I believe based on the clear seeker heads and fins this is a AH-1G with Hellfire missiles:

[img]http://Photo Sharing and Video Hosting at PhotobucketSo is it unusual or not?

Ray

51

I don’t see a thing that says you’re wrong. Since the hellfire required a laser designator to show it where to go, that funny looking nose cap may house the laser. Wonder how the gunner used it. I don’t see an obvious sighting unit. Maybe the laser beam was very visible at the range it was being tested. Sure seems it would be difficult during daylight hours without some sort of sight to focus on the target, a sight slaved to the laser would be the obvious choice but then again I never would have thought about a G model airframe being used to validate the system. Guess they considered the employment on the CObra long before the Apaches came online. Maybe that’s why the TOW was as high a system the Cobra got, it was not intended to be Hellfire equipped.

Chief Snake

52

Chief,

Thanks. What do you make of the middle missiles? It looks to me like there are three on each weapon pylon and the middle one doesn’t seem to have the clear seeker head. Maybe nothing, but that’s what it looks like to me. I think you may be right about the nose cap housing the laser. Good call on that one!

Ray

53

You know how the Apache carries 4 missiles under each pylon? I’ve seen missiles mixed like that on our sister batallion’s Apaches (1st BN/ 1st AVN regt.) when we went to the field together. Not sure what the deal is though.

54

Having shot many Hellfires, Sidewinders, and Sidearms off Cobras, I know that Cobras evolved well beyond TOW. In fact I believe the Marine Cobra loadout is more versatile than any other type Helo. I know you were probably talking Army Cobras Chief but I had to rub that in. [;)]

As for the picture… the thing on the nose looks like a laser spot tracker vice a laser designator. Of course for the validation (or operationally for that matter) you don’t need an onboard designator. AH-1Ws carried Hellifires for years before they got an onboard designator.

The middle missile looks like it could be a dummy missile - just there for the weight.

I’ve got a picture of an AH-1J carrying Hellfires that I’ll post when I find it.

55

56

Supercobra,

Thanks for the pic. 8 hellfires seems to be the norm. Did you ever fly with the 6 missile loadout?
Ray

57

Hey guys,

Yes, that is, in fact a laser designator in the nose of that G model Cobra. Ya beat me to it Ray! The triple missiles were an experimental configuration (brought back for the Comanche, but it died with the program). The center missiles are dummies while the outer ones have live seeker heads. Those triple racks interfered with the inboard pylons, so they were done away with. Plus, the Hellfire was developed sorta concurrently with the Apache, so they didn’t see much reason to put the Hellfire on the Snake, since it is bigger and heavier than the TOW.

As far as Apache Hellfire loadouts, I’ve flown with six on board (all dummies or training missiles, mind you) plus an FCR and she handled like a pig. Gimme 2 missiles and full pods any day!

Jon

58

Jon,

Thanks for the info. I knew you would knwo about that one. Sorry I stole your thunder. I should really stick to Hueys anyway, but I thought maybe you had missed it in the thousands of photos. My hats off to you, Chief and Supercobra, you guys are the Snake Charmers![C):-)]

59

Funny you say that. In 1991 when I was working at the Intrepid, I was working on their F-4N and designed a “what if” piece of nose art for her. Since she flew with the Marine “Diamondbacks”, I called the nose art “Snake Charmer”. That nose art has evolved with my interest in rotary wing aviation. Since then it has adorned every flight helmet I’ve ever flown with!

Jon

60

have you flown with a 250 gal. tank on your inboard yet?