McDonnell / Teledyne Ryan Model 268 XST & Ryan's Stealth UAVs

If the July 1966 label is right, this might be the grandaddy of them all :)
 

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overscan (PaulMM) said:
Sandy Hook / Model 246 - looks like the low RCS demonstrator bottom left.

https://flic.kr/p/UsWxyN
View: https://www.flickr.com/photos/sdasmarchives/34435423066/
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This appears to be the "PINE RIDGE", I believe to be the Model 246:

From CIA Document C06099010, "The Central Intelligence Agency and Overhead Reconnaissance: The U-2 and OXCART Programs", 1954- 1974, 1992

PINE RIDGE
While work was still in progress on low-altitude, short-range reconnaissance systems like AQUILINE and AXILLARY, CIA scientists and engineers were also working on a high-altitude recoverable unmanned reconnaissance vehicle with an extremely-low-radar cross section that would enable it to fly undetected· over hostile territory. During !he 1960s !here had been a study conducted by 1he Teledyne Ryan Aeronautical Company of San Diego on !he construc1ion of an undetectable drone known as SANDY HOOK. This 44-fool long drone would operate at 120,000 feet at Mach 0.9. with a range of 5,000 nautical miles. Its radar cross section would be 0.01 square meters. Project SANDY HOOK never advanced very far in development; projected high costs and substantial technical risks led to its cancellation in December 1969.
Some of the concepts in SANDY HOOK were carried over into a new project known as PINE RIDGE, which was a proposal for an unmanned reconnaissance vehicle. with an even lower radar cross section (0.001 square meter). Research on SANDY HOOK had indicated that a radar cross section this low was attainable and would prevent detection and !racking by existing radar defense systems. The PINE RIDGE proposal called for a delta-shaped vehicle, approximately 17 feet long with a 21-fool wingspan. Two vertical stabilizers would give the vehicle an overall height of three to four feet. An existing Teledyne J-100-CA-100 Turbojet engine could have been used to power !he vehicle. at Mach 0.9 at the operating altitude of 65,000 to 75,000 feet. Range was estimated at 3.300 nautical miles.
Despite interest within !he CIA and !he Air Force for an undetectable reconnaissance vehicle, PINE RIDGE was never funded. In January 197l high-level representatives from DOD and C!A rejected a proposal for a feasibility study to be conducted by Ryan Aircraft.
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There is CIA records retirement request that includes SANDY HOOK, PINE RIDGE, and related files:

RECORDS RETIREMENT REQUEST | CIA FOIA (foia.cia.gov)

www.cia.gov www.cia.gov

This lists the SANDY HOOK as Model 244. There is a Model 246 that has the name/project redacted, I believe this is the PINE RIDGE. Based on this and information from other sources I believe that models of PINE RIDGE were built and tested on the ground. This lead Ryan to push USAF and DoD to create a low RCS vehicle prototype program as of the Packard prototyping programs in 1971-72. This resulted in the low RCS vehicle study. Later that work was applied to the Mini-RPV program.

I believe this the Model 244 SANDY HOOK:
And this may have been an earlier design:

Note that Eberhard, in "Air Force UAVS: The Secret History" states that SANDY HOOK had "hydrogen engines", with the former project manager as his source.

Interestingly enough, the CIA records retirement request lists several other projects:
"COMPASS HAT", may be a different program or the USAF name for SANDY HOOK or PINE RIDGE.
"AXUMITE" , given the naming convention and time period I suspect this was a small RPV program.
 
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Respectfully partly disagree.

Pine Ridge is Model 246, but is the smaller drone - note the dimensions match the drawing in the Have Blue book. PineRidge.jpg


Model 244 Sandy Hook is the earlier, larger (44ft length) iteration

34091361210_731a91599e_o-jpg.579039


34281743081_eaa482feae_o-jpg.579096


Later Sandy Hook? (tail modified)

34410719795_e4daae65ec_o-jpg.579100


Seems between Pine Ridge and Low RCS demonstrator, maybe a later iteration:

tra-d7426-rd119-jpg.379211

while the Model 237 Low RCS Demonstrator Vehicle had a 134 in wingspan indicating it was about half the size compared to Model 246 Pine Ridge.

trw-stealth-jpg.379205


This slide isn't wrong I just misread it. "Sandy Hook" refers to the top images. Model 246 refers to the bottom right or left (or both) image.

34435423066_f3d4ffc534_o-jpg.579037
 
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The second was a 125,000-foot altitude, intercontinental,
subsonic drone with hydrogen engines and very stealthy
delta wing design built by Teledyne Ryan Aeronautical in
the early 1970s. It was to be completely invisible to radar at
that altitude because it had a radar cross-section of a dime.
The proposed $400 million program, called Sandy Hook,
never made it to flight test. The development costs for
both UAVs probably never exceeded $30 million. Robert
R. Schwanhausser, Ryan’s Sandy Hook program manager,
interview, July 7, 1999.
Click to expand...
Eberhard, "Air Force UAVS: The Secret History"
 
PROJECT "PINE RIDGE FILES"
  • VIEWGRAPHS (114 TOTAL) ON CONCEPT OF OPERATION, COST, ENGINE, XHKNXNXXXSXX MODE OF OPERATION, RECOVERY, RESPONSE TIME, THREATS, SPECIFICATIONS, AND MISSION PROFILE.
  • MITRE-LOW RADAR CROSS SECTION RECONNAISSANCE VEHICLE.
    DDC REPORT # T15942 9 MAR 72, RADAR- CROSS-SECTION REDUCTION (C-178)
  • PHOTOS OF _____________ DRONE.
  • TELEDYNE PUBLICATION - MODEL _____________
  • BLUEPRINTS ON THE _____________ DRONE
  • TELEDYNE PUBLICATION - MODEL 246 ____________
  • TELEDYNE PUBLICATION MODEL 244 "SANDY HOOK"
  • TECHNICAL DATA TELEDYNE RYAN ____________ PRICING SUMMARY
  • AXUMITE -- BLUEPRINTS (1 FOLDER)
  • CAMERAS AND SYSTEMS FOR THE DRONE ____________
  • MITRE PROPOSAL FOR ____________
  • ____________ Cy # 1, CRITIQUE OF MITRE/OSA STUDY ON RADAR CROSS SECTION REQUIREMENTS FOR FUTURE RECONNAISSANCE VEHICLE.
  • R&D/OSA FOLDER GENERAL CORRESPONDENCE AND PUBLICATIONS ON THE RYAN DRONE.
  • TELEDYNE PUBLICATION "THE FIREBEE(I
  • DOCUMENT TITLED "U.S. RECONNAISSANCE OPTIONS IN EVENT OF SATELLITE DENIAL".
  • "COMPASS HAT" INFORMATION - WORKING PAPERS - ____________
  • BOOKLET ON TELEDYNE RYAN AERONAUTICAL FACILITIES (PHOTOS OF PLANTS
  • SAS FILE ON GENERAL CORRESPONDENCE ON THE DRONE USES AND CHARACTERISTICS FOR PROJECT ____________

RECORDS RETIREMENT REQUEST | CIA FOIA (foia.cia.gov)

www.cia.gov www.cia.gov
Isn't it a bit odd to redact "PINE RIDGE" from the titles of referenced docs when the doc itself is titled PINE RIDGE FILES?
 
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Only reference to COMPASS HAT is 'AFRDR - 14 Sep 1973 - Special Access Program".

www.google.co.nz

Administrative Practices

www.google.co.nz

Most COMPASS projects are avionics related but there are drone projects like COMPASS ARROW (Ryan AQM-91 Firefly), COMPASS COPE, etc. COMPASS was assigned to USAF Headquarters (AFRDR) - AFRDR stands for Air Force Director of Reconnaissance and Electronic Warfare.

SANDY was assigned to USAF AU (Air University) which is a bit odd?

PINE doesn't seem to be an Air Force assigned code.

MITRE is https://en.wikipedia.org/wiki/Mitre_Corporation

OSA - Office of Special Activities
 
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My only arguments against this being Sandy Hook

1686913262549.png

are

1) We have a figure of 44ft length. If this is Sandy Hook then it is fracking enormous. A delta shaped aspect ratio design of 44ft is more believable. If the aspect ratio of Sandy Hook was the same as Pine Ridge, span would be 54 ft.

2) The "Sandy Hook" writing on the Ryan slide above would then be completely incorrect.

3) Sandy Hook, Pine Ridge and the low-RCS demonstrator seem to be more closely linked program and designwise.
 
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My dear PaulMM,

if that was not from Ryan,what was it ?.
 
That thread is truly fascinating. I was wondering how COMPASS ARROW "semi stealth" related to "full stealth" Lockheed Have Blue a decade later... now I have an answer.
 
overscan (PaulMM) said:
Only reference to COMPASS HAT is 'AFRDR - 14 Sep 1973 - Special Access Program".

www.google.co.nz

Administrative Practices

www.google.co.nz

Most COMPASS projects are avionics related but there are drone projects like COMPASS ARROW (Ryan AQM-91 Firefly), COMPASS COPE, etc. COMPASS was assigned to USAF Headquarters (AFRDR) - AFRDR stands for Air Force Director of Reconnaissance and Electronic Warfare.

SANDY was assigned to USAF AU (Air University) which is a bit odd?

PINE doesn't seem to be an Air Force assigned code.

MITRE is https://en.wikipedia.org/wiki/Mitre_Corporation

OSA - Office of Special Activities
Click to expand...

"Sandy Hook" (and "Pine Ridge") were two-word "place name" code words (cryptonyms) assigned and used internally at TRA (Teledyne Ryan) for projects pursued in their Advanced Design organization. These projects may (or may not) have had a Ryan project number later assigned (as did the Models 244 and 246) depending if the project progressed to further development and/or customer study funding. Timeframe of usage appears to be 1967-1975.

No, there is not a [known] canonical list. (*sigh*). However, "Port Lyautey", "Cape Delgado" and "Seal Rock" have been noted. None of these projects were as ambitious as Sandy Hook or Pine Ridge, were directed to the same requirements, nor did they come to fruition.
 
quellish said:
quellish said:
"AXUMITE" , given the naming convention and time period I suspect this was a small RPV program.
Click to expand...

In "National Reconnaissance Program crisis photography concepts, part 2: PINTO" , https://www.thespacereview.com/article/4526/1 , the author mentions AXUMITE as an F-4 launched satellite system, with hints that a subsequent article may cover it.
Click to expand...

Holy Bayer-matrix dithering Batman ! (edit: note to moderators: please move to new/other topic as appropriate)

The AXUMITE concept is based on the development of a small, very quick recation photo satellite system launched from an F-4 aircraft based in the Pacific. A typical mission would consist of launch within two hours of decision, one time coverage of the selected target area and Atlantic or Pacific reentry vehicl recovery. The booster would be based on the SKYBOLT solid rocket with Scount solid strap-ons. The camera would be a 32-inch focal length scaled up version of the CORONA camera yielding three-foot resolution at 75 nautical mile altitude. The reentry vehicle would be a scaled down version of the MARK V RV.
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1686598322025.png
F-2022-00030_C05137583 AXUMITE BRIEFING SUMMARY
 

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overscan (PaulMM) said:
3) Sandy Hook, Pine Ridge and the low-RCS demonstrator seem to be more closely linked program and designwise.
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Taken from minutes of NRP Executive committee meeting Jan. 29th, 1971:

PINE RIDGE
Dr. McLucas continued that two years ago there was a drone program called SANDY HOOK. It had a 30-foot wing span, flew at 120,000 feet, and had interesting characteristics among which was that it cost $500M to develop. Thus the ExCom decided not to proceed. Air Force funding was terminated. As a consequence the contractor, Ryan Aeronautical Corporation, approached the CIA for a continuation. The present thinking is to build a one-third scale version producing a radar cross-section one-tenth that of SANDY HOOK flying it lower with a developed engine and bringing the total cost down to one-tenth.
Dr. McLucas said he had considered spending $250K to $500K to find out if it were possible to build a .001 square meter cross-section drone complete with camera window.
Click to expand...
 

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Dew said:
quellish said:
quellish said:
"AXUMITE" , given the naming convention and time period I suspect this was a small RPV program.
Click to expand...

In "National Reconnaissance Program crisis photography concepts, part 2: PINTO" , https://www.thespacereview.com/article/4526/1 , the author mentions AXUMITE as an F-4 launched satellite system, with hints that a subsequent article may cover it.
Click to expand...

Holy Bayer-matrix dithering Batman ! (edit: note to moderators: please move to new/other topic as appropriate)

The AXUMITE concept is based on the development of a small, very quick recation photo satellite system launched from an F-4 aircraft based in the Pacific. A typical mission would consist of launch within two hours of decision, one time coverage of the selected target area and Atlantic or Pacific reentry vehicl recovery. The booster would be based on the SKYBOLT solid rocket with Scount solid strap-ons. The camera would be a 32-inch focal length scaled up version of the CORONA camera yielding three-foot resolution at 75 nautical mile altitude. The reentry vehicle would be a scaled down version of the MARK V RV.
Click to expand...

View attachment 701405
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F-2022-00030_C05137583 AXUMITE BRIEFING SUMMARY
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Oh, how I hope this was actually used!

That's one heck of a useful capability.
 
Scott Kenny said:
Oh, how I hope this was actually used!

That's one heck of a useful capability.
Click to expand...

Unfortunately just another interesting paper exercise:

The AXUMITE concept was not the subject of a funded study. It is similar in many respects to FASTBACK but has even more stringent payload weight constraint in the F-4 launched version. Being a one-day system like FASTBACK, AXUMITE could not provide sustained daily coverage of a crisis area. Atlantic recovery is not practical for the same reasons. Further reason for eliminating AXUMITE from further consideration is that the concept has not been developed sufficiently to warrant confidence in the cost and performance estimates.
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from this
 
Dew said:
Scott Kenny said:
Oh, how I hope this was actually used!

That's one heck of a useful capability.
Click to expand...

Unfortunately just another interesting paper exercise:

The AXUMITE concept was not the subject of a funded study. It is similar in many respects to FASTBACK but has even more stringent payload weight constraint in the F-4 launched version. Being a one-day system like FASTBACK, AXUMITE could not provide sustained daily coverage of a crisis area. Atlantic recovery is not practical for the same reasons. Further reason for eliminating AXUMITE from further consideration is that the concept has not been developed sufficiently to warrant confidence in the cost and performance estimates.
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from this
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Bugger.

Still may explain where Dale Brown got some of the idea for the "NIRTS-sats", the Need It Right This Second satellites. Air launched from a 747 or similar widebody airliner instead of from a B52 like the Pegasus booster.
 
Dew said:
PINE RIDGE
Dr. McLucas continued that two years ago there was a drone program called SANDY HOOK. It had a 30-foot wing span, flew at 120,000 feet, and had interesting characteristics among which was that it cost $500M to develop. Thus the ExCom decided not to proceed. Air Force funding was terminated. As a consequence the contractor, Ryan Aeronautical Corporation, approached the CIA for a continuation. The present thinking is to build a one-third scale version producing a radar cross-section one-tenth that of SANDY HOOK flying it lower with a developed engine and bringing the total cost down to one-tenth.
Dr. McLucas said he had considered spending $250K to $500K to find out if it were possible to build a .001 square meter cross-section drone complete with camera window.
Click to expand...
Click to expand...

Notably, SANDY HOOK was to use slurry hydrogen as fuel.
 
Dew said:
overscan (PaulMM) said:
3) Sandy Hook, Pine Ridge and the low-RCS demonstrator seem to be more closely linked program and designwise.
Click to expand...

Taken from minutes of NRP Executive committee meeting Jan. 29th, 1971:

PINE RIDGE
Dr. McLucas continued that two years ago there was a drone program called SANDY HOOK. It had a 30-foot wing span, flew at 120,000 feet, and had interesting characteristics among which was that it cost $500M to develop. Thus the ExCom decided not to proceed. Air Force funding was terminated. As a consequence the contractor, Ryan Aeronautical Corporation, approached the CIA for a continuation. The present thinking is to build a one-third scale version producing a radar cross-section one-tenth that of SANDY HOOK flying it lower with a developed engine and bringing the total cost down to one-tenth.
Dr. McLucas said he had considered spending $250K to $500K to find out if it were possible to build a .001 square meter cross-section drone complete with camera window.
Click to expand...
Click to expand...

30 ft wing span seems wrong for SANDY HOOK - combined with previously known length of 44ft - means it is less flying wing and more flying body.... though this does aid my argument that this (top left) is SANDY HOOK - it appears to have longer fuselage than wingspan.

34435423066_f3d4ffc534_o-jpg.579037

SANDY HOOK was an NRO reconnaissance effort.

If PINE RIDGE was a 1/3rd geometric scale version of SANDY HOOK it would have been very small indeed (10ft span). PINE RIDGE is described as 17ft length, 21 ft span elsewhere.

There's a reference later on in this document to giving PINE RIDGE over to the air force.

Incidentally I saw the minutes posted above say they must be handled by the BYEMAN security control system. This explains the origin of the name of forum user @Byeman
 
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overscan (PaulMM) said:
30 ft wing span seems wrong for SANDY HOOK - combined with previously known length of 44ft - means it is less flying wing and more flying body.... though this does aid my argument that this (top left) is SANDY HOOK - it appears to have longer fuselage than wingspan.
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Even within Ryan's own documents for these projects the dimensions are inconsistent. In a given document measurement X is 200 in one place, 260 in another. It's hard to say which of any of these numbers is accurate or correct. Or the dimensions given do not add up to the area given, etc.

Generally though, SANDY HOOK is approximately 5 times the size of PINE RIDGE or the Low RCS Vehicle. I do not think it was the same delta configuration as those vehicles though (still waiting on new information that should confirm or refute).

overscan (PaulMM) said:
If PINE RIDGE was a 1/3rd geometric scale version of SANDY HOOK it would have been very small indeed (10ft span). PINE RIDGE is described as 17ft length, 21 ft span elsewhere.
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overscan (PaulMM) said:
There's a reference later on in this document to giving PINE RIDGE over to the air force.
Click to expand...

It was (probably) given to the Air Force , and in turn became the basis for the Low RCS prototype effort that was part of the Packard prototypes (LWF, etc.). Packard was briefed on PINE RIDGE and SANDY HOOK by NRO (and CIA).
 
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quellish said:
Notably, SANDY HOOK was to use slurry hydrogen as fuel.
Click to expand...


As for SANDY HOOK, on which only a few million dollars have so far been spent, it was agreed that this was an interesting program from the technology standpoint and that we should go ahead with the $10 million programmed in 1970 but should hold off on systems start. There are various questions related to materials for the drone, the engine and radar absorption materials which can be answered by a continuing technology program; also, the usefulness of slurry hydrogen as aircraft fuel appears interesting for further exploration.
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I use to say the 1965-1975 era at the NRO is the most fascinating, as post-SR71 studies (the ultimate spyplanes) crossed path with a variety of exotic spysats... and drones: Lockheed D-21 and Ryan wonders.
At some point during that decade, spyplanes, spysats and spy... drones overlapped for a) crisis reconnaissance and b) Lop Nor monitoring. It always baffled me that TAGBOARD and COMPASS ARROW were to spy the same place the same way (stealth drones to Lop Nor) yet AFAIK, their developments were almost 100% independant; and parallel. The only thing they have in common is, Nixon-to-Mao's China, 1972, instantly screwed them into oblivion. D-21B at least made a few flights (with very mixed results), but COMPASS ARROW made exactly zero flights. And in both cases, a few dozens drones, insanely expensive and most advanced ever, ended at an aircraft boneyard... or scrapped.
 
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Archibald said:
And in both cases, a few dozens drones, insanely expensive and most advanced ever, ended at an aircraft boneyard... or scrapped.
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Mr. Packard said tha.t he was not sure we can obtain per- mission from the 40 Committee to operate the drone over denied territory. A good example is the TAGBOARD program. Mr. Helms said that he was not enthusiastic about· PINE RIDGE, not only was there a policy question of its ~se but he would question what it could be used against. Mr. Packard said that it was not a question of radar cross-section, it was a question of reliability. After all, the drone might come down in Peking. Dr. McLucas noted that such circumstances had a finite probability--an Army general flew into Russia recently in a manned aircraft.
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At that point they were concerned that a drone flying over denied territory would come down in denied territory, and that would be a problem.
 
Fact is, out of four failed D-21B flights, the first (11/1969) ended as a gift to USSR in Siberia; and the fourth and last, as a gift to the PRC (March 1971). All this because the first failed to make a 180 degree turn after Lop Nor. While the second one did turned correctly, it fell inside China on the return leg (facepalm).
 
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quellish said:
Dew said:
PINE RIDGE
Dr. McLucas continued that two years ago there was a drone program called SANDY HOOK. It had a 30-foot wing span, flew at 120,000 feet, and had interesting characteristics among which was that it cost $500M to develop. Thus the ExCom decided not to proceed. Air Force funding was terminated. As a consequence the contractor, Ryan Aeronautical Corporation, approached the CIA for a continuation. The present thinking is to build a one-third scale version producing a radar cross-section one-tenth that of SANDY HOOK flying it lower with a developed engine and bringing the total cost down to one-tenth.
Dr. McLucas said he had considered spending $250K to $500K to find out if it were possible to build a .001 square meter cross-section drone complete with camera window.
Click to expand...
Click to expand...

Notably, SANDY HOOK was to use slurry hydrogen as fuel.
Click to expand...
No way can a hydrogen powered aircraft fly that high or that far with that claimed size. Hydrogen energy density sucks. I'm talking 14 liters per kilogram of liquid hydrogen, and a quick google says that slush is only 20% denser, for a density of about 11.667 liters per kg. JP7 is about 0.66 liters per kg. Oh, and slush hydrogen needs to be kept at 13.8K, which means even more volume taken up by insulation.
 
It was a big boy
 
Scott Kenny said:
No way can a hydrogen powered aircraft fly that high or that far with that claimed size. Hydrogen energy density sucks. I'm talking 14 liters per kilogram of liquid hydrogen, and a quick google says that slush is only 20% denser, for a density of about 11.667 liters per kg. JP7 is about 0.66 liters per kg. Oh, and slush hydrogen needs to be kept at 13.8K, which means even more volume taken up by insulation.
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There is slush hydrogen, and there is slurry hydrogen. Slurry hydrogen has 1.5-2.0 times the energy density of liquid hydrogen. In the referenced document they *say* "slurry", but could mean either. I have not been able to determine the state of the art in slurry hydrogen during the relevant time period but I think it likely this was referring to an ammonia hydrogen slurry.
 
quellish said:
Scott Kenny said:
No way can a hydrogen powered aircraft fly that high or that far with that claimed size. Hydrogen energy density sucks. I'm talking 14 liters per kilogram of liquid hydrogen, and a quick google says that slush is only 20% denser, for a density of about 11.667 liters per kg. JP7 is about 0.66 liters per kg. Oh, and slush hydrogen needs to be kept at 13.8K, which means even more volume taken up by insulation.
Click to expand...

There is slush hydrogen, and there is slurry hydrogen. Slurry hydrogen has 1.5-2.0 times the energy density of liquid hydrogen. In the referenced document they *say* "slurry", but could mean either. I have not been able to determine the state of the art in slurry hydrogen during the relevant time period but I think it likely this was referring to an ammonia hydrogen slurry.
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Okay, so it's ammonia-hydrogen slurry, which now only takes up 7 liters per kg. JP7/kerosene still only takes up 0.66 liters per kg.
 
RYAN LOW RCS VEHICLE (1973-4 DESIGN STUDY)

The Remotely Piloted Vehicle (RPV) Special Projects Office at Wright-Patterson Air Force Base, Ohio, conducted studies in conjunction with Teledyne Ryan and other companies, of low RCS drones. The Ryan Low RCS Vehicle was to consist of a small metal centerbody surrounded by a large amount of lossy dialectric material. The configuration was all-wing, with a simple delta planform and inward-canted twin vertical tails. The engine and equipment were buried in the fairly thick wing root. Tail surfaces and other features were to be made of "radar- transparent" materials (ref. 23). Although impressive RCS results were achieved in model tests, the approach was impractical and the vehicle still did not meet RCS goals at all frequencies of interest (ref. 19). The goals had been derived from extensive threat analyses, and covered a broad range of frequencies corresponding to the various elements of the latest Soviet air defense systens

References

19. Twigg, John K., Colonel, USAF (Ret), Interview with David C. Aronstein, 24 April 1996.

23. Wintersdorf, R.W., "RPV - Drone Applications," in Proceedings of the 1975 Radar Camouflage Symposium. Air Force Avionics Laboratory Technical Report AFAL- TR-75-100
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Source:

David C. Aronstein - The Development and Application of Aircraft Radar Cross Section Prediction Methodology (SAE Transactions)
 
overscan (PaulMM) said:
Dew said:
Not sure if this should go here or the 262 thread (or neither!) :

View attachment 701665

Compare with the patent sketch in first post. It was from LaRC image library
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URL?

Given the date in the filename and how generic the shape is, not sure if its related.
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aside from materials, does seem to match the description you posted of the Ryan stealth drone. And metal models were preferred at the time for wind tunnel tests, so it certainly could be a wind tunnel model of the Ryan drone.
 
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