Apr 112018

Some old-school animation showing the AH-56 as a recon and targeting vehicle being used in Someplace Much Like Viet Nam. If you’re at all like me, you’ll watch this and think, “I don’t recall this episode of Jonny Quest.”


 Posted by at 2:10 pm
Feb 182018

A few decades before the “X-Wing” configuration gained a measure of popularity, Hughes Tool Company made a detailed study of a somewhat similar concept, the “rotor/wing.” This was a three-bladed helicopter rotor attached to a large central lifting surface, either a circular disk or a triangular structure. The rotor was not turned the conventional way with a turbine engine turning a drive shaft, but instead the engine exhaust was ducted through the center and then out to nozzles at the tips of the rotors. Jet thrust would spin the rotors without transmitting torque to the rest of the vehicles; as a consequence only a small tail rotor would be needed, just powerful enough to orient the craft at low airspeeds.

A few configurations were produced, most of which looking much the same. Probably the most well known configuration was shown in US VTOL Projects 01. Shown below is a lesser-known configuration designed for anti-submarine use. Normally the configurations included the turbojet engines within the upper fuselage, close to the hub of the rotor, but this one rather bizarrely put the engines on the tail. No obvious means of ducting the exhaust to the rotor is evident, so presumably a third (or even fourth) engine was tucked into the fuselage somewhere.


 Posted by at 2:21 am
Feb 132018

Now available: two new US Aerospace Projects issues. Cover art was provided by Rob Parthoens, www.baroba.be

US VTOL Projects #2

US VTOL Projects #2 is now available (see HERE for the entire series). Issue #2 includes:

  • SOS Interceptor: A US Navy Mach 3 aircraft with jettisonable wings
  • Lockheed GL-224-3: A small battlefield surveillance and ground attack plane
  • Phalanx Dragon MP-18: An unconventional  small civilian transport
  • Lockheed L-161-1: An early concept for a variable geometry roadable helicopter
  • GE Supersonic V/STOL: A supersonic strike fighter with flip-out lift fans
  • Convair ANP-VTOL: A nuclear-powered ground-effect craft of the Navy of unusual configuration
  • Piasecki 16H-3: A compound helicopter for high speed passenger transport
  • Boeing Vertol Model 147: A tilt-wing close support fire support design for the US Army

USVP #2 can be downloaded as a PDF file for only $4:


US Research & Recon Projects #2

US Research & Recon Projects #2 is now available (see HERE for the entire series). Issue #2 includes:

  • Lockheed A-1: The first true design leading to the SR-71
  • Bell MX-2147 Model 105: The high altitude “X-16”
  • Boeing/CRC/AMROC X-34 Reference Configuration: A reusable launcher test vehicle
  • Martin Model 159: A scout/observation float plane
  • NASA-Langley Low-Boom Demonstrator: a recent design to demonstrate quiet SST tech
  • McDonnell-Douglas DC-9 Super 80 Propfan Configuration 1: A fuel efficient transport demo
  • Convair “HAZEL” MC-10: An inflatable Mach 3 plane for the Navy
  • Republic Manned Hypersonic Reconnaissance Vehicle: an early scramjet concept


USRP #2 can be downloaded as a PDF file for only $4:


 Posted by at 12:53 pm
Jan 092018

The Curtiss-Wright X-19 was a reasonably successful experimental tilt-prop VTOL aircraft from the first half of the 1960’s. Two aircraft were built; one crashed, one is at the USAF Museum in Dayton (I believe it’s in a restoration facility). The Defense Technical Information Center has two CW documents in PDF format that cover the technology of the X-19 in some detail:





One of the documents includes a fold-out three-view diagram of the X-19, scanned in glorious Extra No color two-bit black and white as two separate pages. I’ve stitched them back together and tried to make the diagram look reasonably good; I’ve uploaded the full-rez result of my effort to the 2018-0 APR Extras folder on Dropbox, available to all APR patrons at the $4 level and higher.

Support the APR Patreon to help bring more of this sort of thing to light!



 Posted by at 12:04 am
Dec 302017

The rewards for APR Patrons have been issued. This month:

CAD Diagram: Marquardt hypersonic burning ramjet booster

Diagram: Convair Class VP Airplane High Performance Flying Boat

Document 1: Apollo Exploration Shelter System

Document 2: Chrysler Work Station Capsule (“work pod” for astronauts)

Document 3: Sikorsky S-97 “Raider” brochure


If you are interested in helping to preserve (and get copies of) this sort of thing, consider signing up for the APR Patreon.



 Posted by at 12:06 pm
Dec 142017

The Lockheed AH-56 Cheyenne was without a doubt the niftiest helicopter ever to *almost* make it into production. but, alas, it was ahead of its time… more precisely, ahead of the available technology.

The gunner sat in a seat that could spin 360 degrees (like the gunner in the Gunstar… and if you don’t get the reference, you’ve a geekiness deficiency). The Cheyenne had a pusher prop for very high speed for a helicopter, and small wings to generate lift and offload the rotor at speed. Lockheed had considerable faith in the future of that propulsion concept and incorporated it into designs for civilian passenger transport helicopters such as the CL-1026 9described in US VTOL Projects issue #01).

 Posted by at 7:29 pm
Jul 162017

Every month, patrons of the Aerospace Projects Review Patreon campaign are rewarded with a bundle of documents and diagrams, items of interest and importance to aerospace history. If you sign up, you get the monthly rewards going forwards; the “back issues” catalog lets patrons aid the APR cause by picking up items from before they signed on. The catalog, available to all patrons at the APR Patreon, has been updated to include everything from the beginning of the project back in 2014 on up to February, 2017.

Below are the items from 2016 (and the first two months of 2017):


If you are interested in any of these and in helping to fund the mission of Aerospace Projects Review, drop by the APR Patreon page and sign up. For only a few bucks a month you can help fund the procurement, scanning and dissemination of interesting aerospace documentation that might otherwise vanish from the public.

 Posted by at 12:49 am
Jul 012017

The Pluto nuclear ramjet is often considered one of the crazier (or perhaps more accurately, “badass”) weapons systems ever considered by serious people. In short, it used a nuclear reactor as the heat source for an airbreathing ramjet; it would fly at a few hundred feet altitude at Mach 3 with nearly unlimited range. Several American aerospace corporations vied for the contract; LTV won the contract to build the airframe in 1961. The “Tory” nuclear ramjet was static ground tested with some success, but the program was cancelled in 1964.

Convair gave the concept considerable study from the beginning of the program in 1957 until at least 1961. Their “Big Stick” concept has been reasonably well known, but they had another idea that was somewhat further from the basic idea. It was mentioned in at least two briefings that I’ve come across; some amount of serious work was done on it, but the information I have is fragmentary. The concept was called simply the “Submersible Nuclear Ramjet.”

Pluto and Big Stick were unmanned cruise missiles. They would be launched from the ground with solid rocket boosters (some though was given to launching from ships, subs and aircraft) and would fly “grand tours” of the Soviet Union, spitting out a number of individual nuclear bombs. They would leave in their wake a line of ruin… the shockwaves from their passage would likely shake apart civilian structures, and the reactors would constantly spit out radioactive particles. At the end of the mission the missiles would crash into one final target.

But the Submersible Nuclear Ramjet would work a little differently. For starters… it was manned. There would be a crew on board throughout the mission.

Rather than starting off at some Air Force base, the Submersible Nuclear Ramjet would actually start off as a submarine, floating around on its own in the ocean. Propulsion would be provided by the nuclear reactor, serving as a “water ramjet” by heating seawater and expelling it. Feeding salt water, diatoms, kelp, fish and all the rest of the junk  the ocean has to offer directly through a nuclear reactor seems a bit dubious.

When the order to begin an actual mission comes in, the propulsion system would be reconfigured from seawater-burning ramjet to seawater-burning rocket. The vehicle would expel stored seawater through the reactor, generating a large amount of thrust, enough to launch the craft vertically out of the water and up to high speed. The craft would then angle over towards the horizontal; the propulsion system would reconfigure once again, this time to an airbreathing nuclear ramjet. The vehicle would then fly a mission essentially similar to Plutos… low altitude, screamingly high speed, ejecting nuclear weapons as it goes. At the end of the mission, unlike Pluto it would *not* crash itself into one final target. Instead, the manned vehicle would return to secure waters and slow to subsonic speed. It would enter a vertical climb and slow to a stop; the ramjet would again reconfigure, this time back to rocket mode. Four drag brakes would deploy around the nose and the vehicle would back down into the water for a soft “splashdown.” It would of course land with nearly empty tanks, so it would be quite buoyant; until the tanks refill, it would likely sit tail-down in the water.

I’m going to try to find out more about this concept, but I have minimal hopes. I’ve gone all this time without hearing about it until just a few weeks ago.

Because why no, I’ve made a basic model of the concept. Complete accuracy is not assured… I have a top view and an inboard profile; as with a distressing number of concept aircraft diagrams, the views seem to conflict on things such as the cockpit canopy, and the inlet configuration is only partially shown. Still, it’s a really interesting concept.

If you’re interested in Pluto, take a look at Aerospace Projects Review issue V2N1. There is a very large, highly illustrated article on Pluto in that issue. If you are interested in the Submersible Nuclear Ramjet, keep an eye on US Bomber Projects… it will show up in the next issue or two.

The renders below show the Convair Submersible Nuclear Ramjet to scale with the LTV Pluto.

 Posted by at 12:36 am
Jun 132017

From the very early 1960’s, this piece of Hughes artwork depicts a hot-cycle “Helibus.” The “hot-cycle” was a briefly studied form of helicopter that did not mechanically drive the rotor, but instead ducted hot exhaust gas from a turbojet up into the rotor hub and then down through ducts in the rotors, exhausting out nozzles near the tips of the rotors. The exhaust gas would then push the rotor blades directly. The advantage was that since there was no direct mechanical linkage between the rotors and the fuselage, the torque that a helicopter normally needs to counter with a tail rotor would be largely eliminated. Thus this “Helibus” has no tail rotor, but it would still need to have some sort of reaction control thrusters at the tail to provide directional control at low speed.

Note that every row of passenger seats has its own door. This would greatly facilitate passenger loading and unloading, at some considerable weight and cost penalty. it would also firmly lock in seat pitch… as the engines are swapped out for newer, better, lighter, more powerful and less fuel hungry versions, the airlines drive would be, as we’ve seen, to pack more and more passengers onboard. But here the doors on the side have to precisely match the seat rows.

A vehicle like this would probably be used mostly to transport office drones from rooftop heliports in urban city centers to transport hubs out in the burbs or the sticks.

 Posted by at 5:23 am