Racescort666

So I was looking into this a bit more and NASA has conducted several tests with inflatable decelerators. HIAD (Hypersonic Inflatable Aerodynamic Decelerator) was the one I was thinking of which is also called Inflatable Reentry Vehicle Experiment (IRVE). The latest flight test was in 2012 which was IRVE-3 and it looks like it would be fairly similar to what ULA wants to do. This project looks to be spearheaded by NASA Langley although an insider told me that Ames also had a hand in it. The latest update I could find was that they were doing some TPS testing with Boeing in 2017. The other inflatable heatshield project is LDSD (Low Density Supersonic Decelerator) which had flight tests in 2014 and 2015 and is lead by JPL. This project also includes the SIAD (Supersonic Inflatable Aerodynamic Decelerator) which doesn't appear to be related to HIAD despite the similarities. LDSD was tested at the US Navy's Pacific Missile Test Range and both missions had successful SIAD deployment however they both also suffered from parachute failure. This I think is maybe a source of confusion for this thread. With regard to inflatable decelerators/heatshields, Ian Clark, principal investigator for LDSD at JPL had this to say after the 2015 LDSD test: With that statement, I'd say this is around TRL 6. It would be up to ULA to decide whether they want to go ahead with using it for engine recovery since NASA seems to be mostly interested in using it to land bigger and better things on Mars. I think it's unlikely that we would see it on Atlas V and probably just on Vulcan but I would be happy to be surprised. Edit: More research yielded this tweet from Jeff Foust: LOFTID is the follow on to HIAD at Langley. Although there isn't much information available on it, it's basically an orbital test of HIAD.

Yes. PSP launch mass (according to wiki) is 685 kg (1510 lbs). Although I did the mass ratio calculation in lbs rather than kg, its all the same for a ratio.

Wiki lists the 3rd stage as a Star 48BV (V is for Vendetta Vectoring) and according to the old Orbital ATK motor catalog, that motor has 292.1s ISP, and 4774 lb and 305.5 lb loaded and burnt out weights. ...calculating... 3557 m/s Edit: Because I'm looking at the spec sheet and said spec sheet lists thrust, the acceleration at burn out is almost 9 g's!

It's worth noting (by my calculation) that a max payload Atlas V 551 upper stage only has 4.6 km/s dV for GTO missions. It's likely that the MECO is much higher than 5 km/s for max payload GTO missions.

I mean... that's ULA's plan... Also, this was the original graphic (and the most amazing graphic I've seen in a formal presentation):

This information is almost impossible to find from the NG website but fortunately the wayback machine has got my back: https://web.archive.org/web/20171107014333/https://www.orbitalatk.com/flight-systems/propulsion-systems/docs/2016 OA Motor Catalog.pdf I don't believe the STAR and Orion motors have much in common.

At a high level (figuratively and literally) you could use the orbital surveys to plot a basic route. This is kind of how they plan roads with a topographic map. Simply having a road wouldn't be enough to say that you could drive flat-out though. Stuff like this: you can drive over but not fast and certainly not at 10 mph and you won't be able to see it easily from an aerial photo:

According to the internet, the top speed of the Lunar Rover is 8 mph and Gene Cernan got it up to 11 (insert "these knobs go to 11" joke). That being said, the 10 mph is with respect to the equator so if you have a cliff in the way, and you have to go perpendicular to the equator, your speed is 0. So yeah, 10 mph average speed is pretty high depending on how much backtracking you have to do. Although, this is only on the equator, the distance to travel is much less at higher latitudes. The part of me that has done off road racing is going "Baja average speed is like 50 mph for top teams..." but that's in a trophy truck that can do 100+ off road over a route that the obstacles are already known. Back on topic a little bit: FH to Pluto. Flyby: sure, KSP has taught me well that flybys are easy. Orbiter: if you don't mind waiting: maybe. If you do mind waiting: not with current technology. Based on the Ice Giant mission proposal by JPL, there are several limitations to current technology. First, FH simply doesn't have the payload capacity to launch an orbiter probe that follows a New Horizons trajectory in a single launch. New Horizons would have had to scrub in the neighborhood of 14 km/s to get into orbit. What about using electric propulsion? Well, the Ice Giant's mission discusses that. For the Uranus orbiter with no atmospheric probe, they proposed using a Solar Electric Propulsion module to gain some energy in the inner solar system before moving out to the gas planets. Unfortunately, this required a 30 kW power system, only gets 5.6 km/s of dV and only works in the inner solar system. Currently, even Kilopower isn't enough (plus it weighs too much) to power something like this. Nuclear propulsion? There is a minimum size to a functioning NTR: 1770 kg plus the added challenge of trying to store hydrogen for 9ish years. What about with other propellants? I've looked into it and it's simply not feasible on a small scale. With a bigger launch mass, maybe. In-space refueling? Now we're talking... although this is something that would fall under new technology. I think it's possible to get an orbiter to Pluto in a reasonable amount of time. In fact, using FH is a reasonable choice to do so. However, new technology needs to be proven out before it can become a reality. I would like to see cryogenic prop transfer, long term cryogenic fuel storage, and NTRs get proven out to make this a reality. Otherwise, it just takes a huge rocket to do it all at once with something that's easy to store. Enter: BFR.

They also have a Kerosene LR 87 there.

So I was interested in bulk densities for the fuels listed (based on common mixture ratios): Hydrolox: 361 kg/m3 Metholox: 864 kg/m3 Kerolox: 1033 kg/m3 A50/NTO: 1202 kg/m3 I wasn't able to find a good density for solid rocket fuel.

https://spacenews.com/boeing-delays-starliner-uncrewed-test-flight-after-abort-engine-test-problem/

To add some perspective, I estimate the F9 upper stage to have 1.7X the dV of a Centaur for the same payload. Falcon 9 and Atlas V fly very different flight profiles though.

Yes, the dV was calculated with an atmospheric nozzle. In the link that @Ultimate Steve posted, the author estimates dV to be in the 4100 m/s range with a vacuum optimized nozzle. There was another blog that did most of the estimation on the engine performance. I'll have to read back up on my rocket engine design to give a good estimate on what I think the BE-3U performance will be. It sounds like 440 s is the best ballpark.

That's an interesting idea but applying this across all government contracts is (in my opinion) unduly unfair to the contractors. There is a high likelihood that the people who work on NASA projects are completely different from the people who work on USAF projects even if they are doing something similar. This is especially true in the bigger companies like Northrop Grumman or Lockheed or Boeing. Military and Civilian projects are usually separated into different groups and the first manager that both groups have in common could be as high as the CEO. Effectively, they're different companies so rating them as if they're the same isn't really comparing apples to apples. That being said, the committee is holding the CEO responsible for the failure of this particular project. To your point Tater, it would make sense in this case.

They are tearing NG apart. Wow. Reading through Jeff Foust's feed is brutal.

Can you send me a link? If they've got information on the BE-3 I'd like to cross check it against my spreadsheet predicting the performance of New Glenn.

O_o this is basic engineering practice. Didn't specify the torque? That's the first question my techs ask when we have them bolt stuff together along with "do we use new fasteners or reuse the old ones?" (The answer is: use new ones, btw.) Or at the very least use one of these:

FIFY

There's a bit of perspective trickery going on there but yeah, Centaur is only 3 m in diameter. 4-5 people could probably put their arms all the way around it like some kind of rocket group hug.

Also, there would be no atmosphere for the engine to run on.

To go along with unofficial stats, the booster Mach number I estimate to be 3.8. It was going ~2600mph at 100,000 ft ASL.

Much easier said than done but even in the last 10 years our tools for analyzing and designing composites have improved significantly. It usually takes a very involved effort to refine and optimize a design. However, this can be helped by optimizer software which, again, has gotten better in recent years. A good composite design is no small task.

Atlas V's shortest 5m fairing weighs 3500kg so I would guess that Falcon 9's fairing would weigh in the 1500kg-1700kg neighborhood per half. This is peanuts considering that Mr Steven's deadweight tonnage (which I had to look up what that was) is 510 t.

I wonder how much different the actual flights will be compared to the test stand. You hypothetically don't have any atmosphere at shutdown but you also have to deal with reentry. Reentry should be much more mild than the shuttle reentry though.