Quote from: Solarsail on 04/25/2020 04:08 pmAccording to this, Talon-A will operate with "an air breathing rocket engine". This sounds new, I think?https://www.janes.com/article/95745/talon-a-hypersonic-testbed-to-achieve-ioc-by-2022Indeed, the article says that's a direct quote from someone on the project (as well as saying that a schematic on the website implies it, which is arguable - I thought that inlet was an optional test configuration, and there appear to be two separate propellant tanks, so they haven't managed "elimination of oxidiser cylinders"). They also suggest it might be some sort of dual-mode rocket/scramjetColor me surprised, and a little concerned. There are a handful of medium-size liquid rocket engines on the market that could suit this vehicle, and choosing to purchase one of them instead of designing one from the ground up sounded like a great idea. There are not any air-breathing liquid rocket engines in operation right now, let alone any for sale and designed for this weight class, AFAIK. Pumping money into Reaction Engines Ltd. and waiting for them to develop one doesn't sound like a great business plan. What other possible suppliers am I missing? Boeing, maybe?
According to this, Talon-A will operate with "an air breathing rocket engine". This sounds new, I think?https://www.janes.com/article/95745/talon-a-hypersonic-testbed-to-achieve-ioc-by-2022
Quote from: Craftyatom on 04/25/2020 07:30 pmQuote from: Solarsail on 04/25/2020 04:08 pmAccording to this, Talon-A will operate with "an air breathing rocket engine". This sounds new, I think?https://www.janes.com/article/95745/talon-a-hypersonic-testbed-to-achieve-ioc-by-2022Indeed, the article says that's a direct quote from someone on the project (as well as saying that a schematic on the website implies it, which is arguable - I thought that inlet was an optional test configuration, and there appear to be two separate propellant tanks, so they haven't managed "elimination of oxidiser cylinders"). They also suggest it might be some sort of dual-mode rocket/scramjetColor me surprised, and a little concerned. There are a handful of medium-size liquid rocket engines on the market that could suit this vehicle, and choosing to purchase one of them instead of designing one from the ground up sounded like a great idea. There are not any air-breathing liquid rocket engines in operation right now, let alone any for sale and designed for this weight class, AFAIK. Pumping money into Reaction Engines Ltd. and waiting for them to develop one doesn't sound like a great business plan. What other possible suppliers am I missing? Boeing, maybe?There were a few retired air breathing rocket engines. Listed a couple below.The upper stage of the old RIM-8 Talos missile with a ramjet engine.The upper stage of the Sea Dart missile also with a ramjet engine.Replicating something similar to the ramjet engines used in those missiles shouldn't be hard.
[Talon-A] will also be capable of autonomous take-off, under its own power, via a conventional runway.
ROC rolled outside today for some stationary testing, no taxi tests or flights just yet. COVID has slowed us down a little over the past few months. We are back now and picking up the pace.
Interestingly, while many recent hypersonic vehicles have had separate boost and sustainer engines - generally a rocket for the former and a scramjet for the latter - I can't see any hint of a scramjet on this design. Stratolaunch may be running a rocket-only hypersonic vehicle, like the old X-15, which would be interesting (and put some extra limitations on "long duration flight at high Mach"). SpaceNews only says that it will be "powered by a liquid-propellant rocket engine", which could be taken both ways. We'll have to wait and see.
DARPA still has the Advanced Full Range Engine AFRE program contracted to NGC and AR. Could the "Z" be a testbed for these engines?https://www.flightglobal.com/darpa-revives-turbine-ramjet-concept-for-hypersonics/120967.articlehttps://www.rocket.com/article/darpa-awards-aerojet-rocketdyne-contract-develop-hypersonic-advanced-full-range-enginehttps://www.defenseworld.net/news/21834/Orbital_ATK_Awarded_DARPA_Contract_For_Hypersonic_Engine_Research_Project#.XoNZeGllDqs
Quote from: starchasercowboy on 03/31/2020 03:02 pmDARPA still has the Advanced Full Range Engine AFRE program contracted to NGC and AR. Could the "Z" be a testbed for these engines?https://www.flightglobal.com/darpa-revives-turbine-ramjet-concept-for-hypersonics/120967.articlehttps://www.rocket.com/article/darpa-awards-aerojet-rocketdyne-contract-develop-hypersonic-advanced-full-range-enginehttps://www.defenseworld.net/news/21834/Orbital_ATK_Awarded_DARPA_Contract_For_Hypersonic_Engine_Research_Project#.XoNZeGllDqsThis would seem an ideal match but has anyone heard anything substantial about this since 2018?OTOH a pure air breathing system (even one that works up to M5) does not need LOX so this doesn't seem right either.
All in a day’s work! This weekend the Stratolaunch team rolled ROC out of the hanger to conduct rigorous cabin pressure tests. All test objectives were successfully completed! More testing to come as our sight is set on our next flight.#THINKBIG #stratolaunch #BreakingBarriers
A behind the scenes peek at the "Impossible Engineering" episode featuring - Stratolaunch. The episode is due to air on The Science Channel September 2 at 9:00 p.m. Such fun filming, can't wait to watch. #THINKBIG #BreakingBarriers #stratolaunch
Opening the massive hangar doors to roll Roc this morning for more test. What a beautiful sight. #THINKBIG #BreakingBarriers #Stratolaunch
Testing components of the @Stratolaunch Talon-A aerodynamic design at @UW Kirsten Wind Tunnel. One step closer to advancing high-speed tech through innovative design, manufacturing and operation of world-class aerospace vehicles. #Stratolaunch #TLGAero #ThinkBig #BreakingBarriers
Another day, another successful test! This successful Pitch Test just got Roc and her crew that much closer to getting back in the air. More test on the way! #stratolaunch #ThinkBig #BreakingBarriers
Basking in the glory of the Mojave sun! More test to conduct this week for Roc, and will soon have visuals to share on the progress of our hypersonic vehicles. #Stratolaunch #ThinkBig #BreakingBarriers
Let's get these fuel tests started! Busy weekend ahead, but no place we'd rather be. #stratolaunch #thinkbig #breakingbarriers
Early test for the rocket engine that will propel the Stratolaunch Talon A hypersonic vehicle to Mach 5+ speeds and beyond. Routine and reliable access to the hypersonic flight regime just got one step closer. #onestepcloser #ThinkBig #BreakingBarriers
https://www.stratolaunch.com/vehicles/talon-aI can't quite figure out what the Talon A will be used for. It can get a "payload" up to Mach 6. They do say briefly "Internal and external experiments" but the "external" part isn't really expanded upon. They also say "The Talon-A is highly instrumented to collect vehicle and payload experiment data". In my simplistic view, unless you're hanging your own aerodynamic structure out in the air stream then what's the use? That is, is there some internal payload that can benefit from high speed testing?
<snip>I can't quite figure out what the Talon A will be used for. It can get a "payload" up to Mach 6. They do say briefly "Internal and external experiments" but the "external" part isn't really expanded upon.<snip>
Quote from: dwheeler on 10/14/2020 12:36 am<snip>I can't quite figure out what the Talon A will be used for. It can get a "payload" up to Mach 6. They do say briefly "Internal and external experiments" but the "external" part isn't really expanded upon.<snip>AIUI mach 5+ hypersonic vehicles historically have a habit of shredding their outer skin and external structures. Just getting a research vehicle to finish a flight while more less intact is a big achievement.Plus how do you get sensor reading with the mach 6 shockwave in front of the nose. Which I believe will generate cone of plasma around the vehicle.
Quote from: Zed_Noir on 10/14/2020 08:31 amQuote from: dwheeler on 10/14/2020 12:36 am<snip>I can't quite figure out what the Talon A will be used for. It can get a "payload" up to Mach 6. They do say briefly "Internal and external experiments" but the "external" part isn't really expanded upon.<snip>AIUI mach 5+ hypersonic vehicles historically have a habit of shredding their outer skin and external structures. Just getting a research vehicle to finish a flight while more less intact is a big achievement.Plus how do you get sensor reading with the mach 6 shockwave in front of the nose. Which I believe will generate cone of plasma around the vehicle.Well I guess that's what I'm having a hard time figuring out. I would think mounting an external payload isn't just a straightforward case of attaching some pod with a pylon... hypersonic aerodynamics makes that a non-trivial thing, ya? I'm thinking of the X-15 ramjet experiment where the dummy ramjet's shockwave basically burned through the pylon. https://blog.seattlepi.com/americanaerospace/2018/10/29/x-15a-2-faster-than-a-speeding-bullet/
Draper Signs Agreement to Provide GN&C for Stratolaunch’s Hypersonic VehicleTHURSDAY, OCTOBER 15, 2020CAMBRIDGE, MA—Precision guidance and navigation is critical to success and safety in spaceflight. Today, as Stratolaunch builds its next generation vehicle for hypersonic flight test, it will be guided by flight software developed by Draper.“As with Draper’s past contributions to the U.S. space program, Draper’s engineers are proud to develop a key component of Stratolaunch’s hypersonic vehicle—guidance, navigation and control (GN&C) software,” said Neil Adams, Draper’s principal director of space systems. “Stratolaunch’s vehicles will travel through the Earth’s atmosphere at speeds of more than 3,800 miles per hour. Stratolaunch presents an opportunity to put Draper’s flight software into a hypersonic flight envelope—one with a slender, low-drag form that can enable sustained maneuvering flight in the atmosphere.”Stratolaunch builds, tests and operates hypersonic vehicles—those that can travel at least five times the speed of sound, or Mach 5. Draper’s flight software will be used on Talon-A, a fully reusable, autonomous, liquid rocket-powered Mach 6-class hypersonic vehicle.Under the multi-year contract, Draper will design, develop and deliver a guidance, navigation and control system for the Stratolaunch reusable hypersonic vehicle. The vehicle is designed for use by government, including the Department of Defense, the commercial sector and academia, which will contract for payload capacity for space or earth applications.Draper’s work on the Stratolaunch vehicle builds on its legacy of support to NASA, which began with Draper’s design of the Apollo Guidance Computer, and has continued with programs including the International Space Station (ISS) and the Space Shuttle. Draper has been a leader in hypersonics for decades, and has provided system evaluations, capabilities including guidance, navigation and control and hypersonic flight test support for its U.S. government customers.
