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CONTEST - Zion Mainframe - The USAF/ DARPA FALCON program

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posted on Apr, 24 2004 @ 08:24 AM

"Force Application and Launch from CONUS (FALCON)"


Initially, I simply wanted to write an article for I had already begun to work on this article, when the DISC-group came up with the 'Call-For-Entries' contest.
Though I was very interested in the contest, I didn't want to be involved in it, because I am a staff member. After thinking it over for a few days, I decided to sign up for it.
Hopefully all the information you find in this article is correct, I compiled this article from several dozen news stories, websites and official document from DARPA.
I also made an HTML version of this article, with a better lay-out and a handy 'help' function for technical terms and shortcuts. Click here for the HTML version

Hopefully you'll enjoy reading this article, I'm looking forward to your comments, and answering questions (if any).



A hypersonic cruise vehicle capable of taking off from a conventional military runway and striking targets as far as 9,000 miles away is one of three aerial vehicles under conceptual development under the Defense Advanced Research Project Agency's FALCON initiative.
It will be developed in two parts with the Small Launch Vehicle (SLV)/ Common Aero Vehicle (CAV) expected to be complete by 2010 and a Hypersonic Cruise Vehicle (HCV) expected by 2025.
The government is seeking a "clean sheet of paper" approach to open the design for SLV boosters and to "think out of the box" to propose unique collaborative designs using creative integration of the latest advances and operations to enable a revolutionary advance in payload lofting capabilities.

Shortcuts explained
- DARPA - Defense Advanced Research Projects Agency
- FALCON - Force Application and Launch from CONtinental United States.
- CONUS - Continental United States
- CONOPS - Concept of Operations
- LEO - Low Earth Orbit
- SLV - Small Launch Vehicle
- HCV - Hypersonic Cruise Vehicle
- HWS - Hypersonic Weapon System
- CAV - Common Aero Vehicle
- ECAV - Enhanced Common Aero Vehicle

Motivation for the program

According to the USAF the current bomber fleet is too slow, and therefor intercontinental missions become too stressfull for pilots.
The US Strategic Command has a critical need for responsive, effective, and affordable conventional strike to provide deterrence, power projection and coercion, delivering
munitions in minutes to hours globally from CONUS (or equivalent reach from alternative US basing).
"While advancements in target identification and precision strike have been abundantly demonstrated, deficiencies in engaging and defeating time-critical and
high value, hard and deeply buried targets (HDBT) have also been revealed", according to the official program motivation.

Goal of the program

As mentioned before, the program has been devided into two projects, a near-term, and a far-term project.

The goal of the near-term project is to build a Common Aero Vehicle (CAV) capable of delivering 1,000 pounds of munitions to a target 3,000 miles away. SLV, a low-cost, responsive launch system is capable of boosting a CAV to the required altitude and velocity.
The vehicle will be put into low Earth orbit (LEO) at a total launch cost of less than $5,000,000 (excluding payload and payload integration costs). The Enhanced Common Aero Vehicle (ECAV) would be a more advanced design that offered substantially greater range and improved manoeuvrability.

The far-term project is to build a HCV, or . This autonomous aircraft would be capable of taking off from a conventional military runway and striking targets 9,000 nautical miles distant in less than two hours.
It could carry a 12,000-pound payload consisting of Common Aero Vehicles (CAVs), cruise missiles, small diameter bombs or other munitions.

Many of the technologies required by SLV are also applicable to the HCV concept such as high lift-to-drag technologies, high temperature materials, thermal protection systems, and periodic guidance, navigation, and control.

Initiated under the Space Vehicle Technologies program, and leveraging technology developed under the Hypersonics program, FALCON will build on these technologies to address the implications of powered hypersonic flight and reusability required to enable this far-term capability.
The FALCON program addresses many high priority mission areas and applications such as global presence, space control, and space lift.
(From DARPA's official mission overview.)

Program Overview

Phase 1 - System Definition ( 3rd Quarter 2003 - 2nd Quarter 2004)

  • Ph1, Task 1: development of conceptual designs, performance predictions, cost objectives, and development and demonstration plans for the SLV.

  • Ph1, Task 2: development of conceptual designs, concepts of operations, and a demonstration plan and identify critical technologies for the Hypersonic Weapon Systems portion of the program, which includes the CAV, the ECAV, and the HCV.

Phase 2 - Design & Develop (2nd Quarter 2004 - 3rd Quarter 2007)

  • Ph2, Task 1: demonstration of and flight-test all significant characteristics of the operational launch vehicle.

  • Ph2, Task 2: Objective is to flight-test a CAV and develop critical designs for Enhanced CAV and HCV demonstration systems incorporating flight-ready hypersonic technologies.

Phase II will execute an integrated plan to evolve both CAV and HCV designs and mature associated critical technologies.

Phase 3 - Weapon System Demonstrations (3rd Quarter 2007 - 2009)

Phase III will consist of a single task identified as Weapon System Demonstrations.
The objective is to flight-test an integrated SLV/ Enhanced CAV system, and flight-test Enhanced CAV and HCV demonstrators to validate system and technology performance.
Phase III will be performed over a 30-month period during which the Enhanced CAV will be flown integrated with the SLV.


Research into hypersonic aerodynamics, heat transfer as it relates to high speed aerodynamics, size and weight of a hypersonic vehicle, flight control systems, materials, thermal management techniques, cooling etc. is essential for the development of the HCV.
Any object-airplane, spacecraft, asteroid-speeding through the atmosphere will compress and heat the air in front of it.
This heat is inevitably absorbed by the surface of the object. Heat buildup just kills most designs for hypersonic aircraft.
The hotter the craft gets, the more material engineers add to the airframe to strengthen and shield it.
Also, most other hypersonic concepts have trajectories that are strictly atmospheric, and the only way to get rid of the heat is to dump it into the fuel and then burn the fuel in the engines.
The problem is, the faster you fly, the more fuel you must carry as a heat sink. Eventually, you end up carrying a significant amount of fuel just as a heat sink, and the engines end up running fuel-rich, that is, burning up more fuel than they really need.
That's wasteful in and of itself. Also, more material and more fuel translate to more weight. After a while, the aircraft can no longer carry a decent cargo
NASA uses two retired USAF SR-71's for research on supersonic/hypersonic aircraft and propulsion systems.
Data from the NASA SR-71 LASRE project will likely be used for the FALCON project.
The government is seeking a "clean sheet of paper" approach to open the design for SLV boosters and to "think out of the box" to propose unique collaborative designs using creative integration of the latest advances and operations to enable a revolutionary advance in payload lofting capabilities.

Propulsion Techniques

Aerospike engine

A major advantage of the aerospike rocket engine is the ability of the nozzle to adjust with altitude changes to the free-stream static pressure, which results in a higher specific impulse than a conventional bell nozzle has at low altitudes.
This altitude compensation is caused by the unique nozzle geometry of the aerospike engine, which has a central ramp terminating in either a plug base or spike in the center and is scarfed, or open, to the atmosphere on the sides.
The nozzle exhaust flow is free to expand on the open sides and self-adjust to staticpressure changes with altitude.
The compensation of the exhaust gases allows the nozzle to run a more optimum conditions than a conventional bell-type nozzle.

Scramjets - Supersonic Combustion Ramjet

Rockets combine a liquid fuel with liquid oxygen to create thrust. Take away the need for liquid oxygen and your spacecraft can be smaller or carry more payload.
Oxygen needed by the engine to combust is taken from the atmosphere passing through the vehicle, instead of from a tank onboard. The craft becomes smaller, lighter and faster.

Under NASA's Hyper-X program and the Propulsion Directorate's Hypersonic Technology (HyTech) program, scientists plan to demonstrate hydrogen- and hydrocarbon-fueled scramjet engines respectively.
In july 2002, the Australina HyShot program succesfully launched a hypersonic, scramjet propulsed rocket, to a speed of Mach 7.6, or 7.6 times the speed of sound.
Researchers predict scramjet speeds could reach 15 times the speed of sound.

Pulse Detonation Wave Engines

As with scramjets, aircrafts with PDWE's do not need to carry liquid oxygen aboard, as air breathers, these PDWEs could theoretically propel a hypersonic aircraft towards Mach 10 at an altitude in excess of 180,000 feet.
Liquid methane or liquid hydrogen is ejected onto the fuselage, where the fuel mist is ignited, possibly by surface heating.
The PDWE works by creating a liquid hydrogen detonation inside a specially designed chamber when the aircraft is traveling beyond the speed of sound.
When traveling at such speeds, a thrust wall (the aircraft is traveling so fast that molecules in the air are rapidly pushed aside near the nose of the aircraft which in essence becomes a wall) is created in front of the aircraft.
When the detonation takes place, the airplane's thrust wall is pushed forward.
This process is continually repeated to propel the aircraft. From the ground the jet stream looks like "donuts-on-a-rope."

Related Programs


The Aurora aircraft is allegedly a secret U.S hypersonic (Mach 5 or greater) spy plane developed in the 1980s or 1990s as a replacement for the aging and expensive SR-71 Blackbird. Aurora aircraft might be based at the secret government airbase Groom Lake (Area 51) in Nevada, as well as Edwards AFB, California, and Machrihanish, Scotland.
While the United States government denies Aurora's existence, many people have pieced together sketchy evidence to the contrary.
The strongest sources lies in a possible eyewitness and trained aircraft spotter named Chris Gibson. In 1989, while working as an engineer on a North Sea oil platform, he saw and drew a picture of an unfamilar triangular-shaped aircraft.
Also, some cite Aurora as the source of several unexplained sonic booms that occurred over California (especially Los Angeles) and Nevada. Mistery Aircraft Aurora/Senior Citizen

NASA X-43/ Hyper-X Project

NASA uses the Hyper-X vehicle to test propulsion technologies that could be applied to future reusable space launchers and hypersonic aircraft.
While vehicles with conventional rocket engines carry oxygen on board, the air-breathing Hyper-X vehicle ingest and compress oxygen from the atmosphere using the vehicle airframe.
This type of propulsion system could potentially increase payload capacity on future vehicles since no onboard supply of oxidizer would be required.
NASA X-43 press release

Super-Valkyrie/ Brilliant Buzzard Bomber/Spaceplane (By Bill Rose for UFO Magazine UK)

There is growing evidence that a mini-shuttle was developed shortly after the space shuttle Challenger disaster on January 28, 1986 and that the trials began in 1992.
Operating under the mysterious Aurora Project, the system is believed to comprise a spaceplane roughly the size of an SR-71 spyplane and a hypersonic launch vehicle resembling the experimental XB-70A strategic bomber designd in 1957-60. This large aircraft could perform a number of roles, but it appears to have been designed specifically to carry the smaller spaceplane to a suitable launch altitude.
Sightings of the aircraft described as a "mothership" first began in the late summer of 1990. It was said to resemble a modernized version of the highly advanced North American XB-70 Valkyrie bomber, developed for the USAF, but never put into production. Designed to achieve high efficiency through a very close integration of propulsion and aerodynamics, the XB-70 could achieve a speed of Mach 3.
Rest of the article

FDL-5 & X-24
In the late 1960s, the Flight Dynamics Laboratory had designed several aircraft shapes which they believed would have good handling carachteristics from Mach 4 up to orbital velocities, but particularly in the range of Mach 8 to Mach 12.
They designated these shapes FDL-5,6 and 7. The shapes were important because their lift to drag ratios were around 2.5, compared with 1.5 for some of the earlier lifting bodies.

Instead of building the new shapes from scratch, it was decided to modify an existing lifting body to one of the shapes to save money.
Originally this was going to be one of Martin's unused SV-5J bodies, retaining the three vertical fins and calling the new shape FDL-8.
In January 1969 the FDL proposed development of a jet powered aircraft along these lines, but rocket propulsion offered more advantages, so the plan was changed to use a currently unused aircraft, the X-24-A.
The USAF FDL projects paved way for future projects involving orbital, transatmospheric and hypersonic flight.

The FDL-5 in lauch, flight, and landing configuration (click to expand);

*Images of the FDL-5 used with friendly permission from


[edit: fixed an error in the code for the shortcuts table]

[Edited on 24-4-2004 by Zion Mainframe]

posted on Apr, 29 2004 @ 11:41 AM

Well-written and very informative!

Is the aerospike engine new technology or existing technology? I wanted to say it's existing but I'm alsow wondering if that forms the basis for our newer thrust-vectoring engines. Am I off-base here?

posted on Apr, 30 2004 @ 07:20 AM
Yes, the aerospike engine is existing technology. It was tested by NASA during the SR-71 LASRE project:

You're a little off-base with the thrust vectoring part, though. The aerospike is a new generation rocket booster engine, designed to replace the traditional bell-shaped engine.

posted on May, 3 2004 @ 10:15 AM
I see, that makes sense now. From the Nasa article, "A final hot-fire flight test did not take place due to the liquid oxygen leaks in the test apparatus. The ground firings and the airborne cryogenic gas flow tests provided enough information to predict the hot gas effects of an aerospike engine firing during flight." The LASRE only hit Mach 1.58 in the tests. Were they able to project expected velocity from those tests or did it ever go faster and I just missed it?

posted on May, 7 2004 @ 09:59 PM
Great job Zion. You are up to your normal excellence. I know you worked hard and it shows. My best from me to you. Keep it up.

regs out...

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