Teledyne Ryan Model 262 'Manta Ray' (STAR)

[TomS]

Slightly more on-topic, the STAR RPV was a staple of some 1970s "advanced marine vehicle" designs. For example, the HYD-7 hydrofoil escort was supposed to carry as many as a dozen RPVs like this.

https://www.secretprojects.co.uk/threads/1300-ton-destroyer-escort-hydrofoil-deh.6969/post-356214

Also the HYD-2, which was more of a true frigate (FFG-7) successor

https://www.secretprojects.co.uk/threads/grumman-hydrofoil-warship-hyd-2.32080/post-356505

 

[TomS]

In case it hasn't been shared before, there is a very interesting study by Teledyne Ryan done in 1976 for the U.S. Army (after the Lockheed "Aquila" was chosen over other designs by TRA, Philco-Ford, etc.) and pertaining to the question of Mini-RPVs, especially focusing on the various possible configurations and methods for recovery.
It can be found online in two places, but I'll attach it here nevertheless, just in case:

• https://apps.dtic.mil/sti/tr/pdf/ADA046177.pdf
• https://archive.org/details/DTIC_ADA046177

And in 1978, a Teledyne Ryan study on various launching techniques for same.

https://apps.dtic.mil/sti/tr/pdf/ADA062990.pdf

 

[_Del_]

It's too bad the earlier Mini-RPV/Low RCS RPV attempts were still secret at the time of the book.

As memory serves they nixed a great deal of content from both that book and the earlier "Fireflies and other UAVs".

 

[overscan (PaulMM)]

But it's a low-altitude battlefield reconnaissance vehicle. And it's built s so that the ground radars couldn't see it hardly at all. See it's got a screen over the engine to hide the engine blades when they turn around

From William F. Bahret interview (https://corescholar.libraries.wright.edu/special_ms431/20/)

I always wondered how Manta Ray was supposed to be stealthy when the propellor blades would give strong returns front and back.

I just realised that these drawings show the screens over the engine, though none of the flown models had them.

 

[quellish]

From William F. Bahret interview (https://corescholar.libraries.wright.edu/special_ms431/20/)

I always wondered how Manta Ray was supposed to be stealthy when the propellor blades would give strong returns front and back.

I just realised that these drawings show the screens over the engine, though none of the flown models had them.

View attachment 745311

The Manta Ray was based on earlier work by Ryan for larger vehicles. I would have to find the reference but scaling down the materials from the larger vehicles to the Manta Ray was not very successful.

 

[Stargazer]

I just realised that these drawings show the screens over the engine, though none of the flown models had them.

True. The mockup had them, though.

 

[overscan (PaulMM)]

True. The mockup had them, though.

I never noticed!

 

[_Del_]

The Manta Ray was based on earlier work by Ryan for larger vehicles. I would have to find the reference but scaling down the materials from the larger vehicles to the Manta Ray was not very successful.

RAM needs to be a certain thickness for best effectiveness, that means weight. Screens introduced all sorts of small burbles that a larger engine might ingest with no issue but may substantially affect the efficiency of a small propeller blade. Also created drag itself. All magnified as a percentage on a smaller design.