Photos Vietnam war helicopter aviation: NOH-6A "The Quiet One"

[Marsch]

The NOH-6A (Night Observation Helicopter) was also called the Hughes 500P ("P" for Penetrator). It was a special version build for the CIA and was optimized for nighttime observations. Therefore it got all kind of IR/Nighttime observation devices (like for example a FLIR). Besides that it also got an acustically optimized engine, rotors, smoothed out gear and transmission and all kind of sound-proofing materials for a better noise reduction. Two helicopters of this type were build.

A NOH-6A infront of its hangar at PS-44 (remote base near Pakse, Laos).

Front view of "The Quiet One".

During evaluations.

With an upgraded FLIR.

The cockpit got FLIR monitors for pilot and co-pilot.

The optimized 5-blade rotor for better noise reduction.

The optimized tail-rotor with 4-blades. Actually it are two rotors with two blades each to better counter the produced noise (the same system is used on the AH-64 "Apache" for the same reason).

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I had looked up the registration/built numbers for the two helicopters years ago and to my surprise one of them is still in use with the Snohomish Sheriff Department, WA.

You can clearly see the four blade tail-rotor here.

I had even contacted said SD and asked if they know what they have there and one of the pilots replied back. He told me that they got it exactly because it's so quiet. So the answer is obviously yes.

 

[Marsch]

An other shot of the cockpit with the FLIR monitors.

If you're wondering what's in the pods it's carrying in some pics. The right one should be an aux fuel tank.

With "hover pod".