Quote from: Steven Pietrobon on 12/09/2018 02:06 amQuote from: HMXHMX on 12/08/2018 03:33 pmGood find. I think this is a team that looks pretty good – they've done real things, so good luck to them. But the vehicle concept looks way too vanilla for my taste, and too small.The engines are ORSC! That's hardly vanilla for a startup. You have to start somewhere. By starting small means they might actually achieve launch. Launch price is about $14M for 650 to 900 kg, depending on orbit.But it is Ursa making the engines and they’ve both been at it a while and have functioning engines on the stand. I’ve been to visit them and came away impressed.
Quote from: HMXHMX on 12/08/2018 03:33 pmGood find. I think this is a team that looks pretty good – they've done real things, so good luck to them. But the vehicle concept looks way too vanilla for my taste, and too small.The engines are ORSC! That's hardly vanilla for a startup. You have to start somewhere. By starting small means they might actually achieve launch. Launch price is about $14M for 650 to 900 kg, depending on orbit.
Good find. I think this is a team that looks pretty good – they've done real things, so good luck to them. But the vehicle concept looks way too vanilla for my taste, and too small.
https://www.ablspacesystems.com/ Scrolling through... looks like they've totally changed their engine plans. No longer lists Ursa as the supplier. Now some gas-generator engines named E1 and E2.The only thing which makes me think these engines aren't in-house is that they've had zero job postings for propulsion analysis/design, aside from systems level stuff. The drawings shown on their website, meanwhile, look pretty high fidelity. Anyone recognize those sketches?
Scrolling through... looks like they've totally changed their engine plans. No longer lists Ursa as the supplier. Now some gas-generator engines named E1 and E2.
Very interesting. Looking at the render posted of E2, there are no apparent valves between the pump and chamber/injector. I bet they are going to try using a pintle with face shutoff; interesting choice considering pintles are relatively inefficient and they don't appear to need the deep throttling capability. The turbine exhaust also appears to be ducted into the nozzle extension.I wonder what drove them away from Ursa Major?
Quote from: Gliderflyer on 12/12/2018 11:23 pmVery interesting. Looking at the render posted of E2, there are no apparent valves between the pump and chamber/injector. I bet they are going to try using a pintle with face shutoff; interesting choice considering pintles are relatively inefficient and they don't appear to need the deep throttling capability. The turbine exhaust also appears to be ducted into the nozzle extension.I wonder what drove them away from Ursa Major?I'd hazard the guess that price per engine might have been the tipping point; Ursa seems to be making excellent technical progress so I doubt it was any technical concern. Given that ABL has hired some Virgin people with propulsion experience, they may now feel comfortable developing powerplants of a type similar to Virgin Orbit's first or second stage in-house.
Quote from: HMXHMX on 12/13/2018 12:10 amQuote from: Gliderflyer on 12/12/2018 11:23 pmVery interesting. Looking at the render posted of E2, there are no apparent valves between the pump and chamber/injector. I bet they are going to try using a pintle with face shutoff; interesting choice considering pintles are relatively inefficient and they don't appear to need the deep throttling capability. The turbine exhaust also appears to be ducted into the nozzle extension.I wonder what drove them away from Ursa Major?I'd hazard the guess that price per engine might have been the tipping point; Ursa seems to be making excellent technical progress so I doubt it was any technical concern. Given that ABL has hired some Virgin people with propulsion experience, they may now feel comfortable developing powerplants of a type similar to Virgin Orbit's first or second stage in-house. Them moving away from Ursa Major actually makes me less confident in their prospects for success, not more. Trying to develop two pump-fed engines quickly sounds like wishful thinking. But I wish them luck.~Jon
The 1000-1500kg LV market is becoming very competitive, I count 5 serious contenders. Firefly, Relativity, Boeing XS1, ABL and PLD of Spain. Firefly seems to be leading one with launch next year.
So it looks like they posted a payload users guide at some point. See https://s3-us-west-2.amazonaws.com/abl-media/rs1_payload_users_guide_v1.pdfNot sure when the website was updated with it, but noticed it tonight when I was scrolling through the front page.Quite a lot of interesting stuff in here -- way more than we've known thus far.
Isn't staging t 3.1 km/sec rather a low velocity?
Quote from: Comga on 01/28/2019 01:07 amIsn't staging t 3.1 km/sec rather a low velocity?No. The Saturn V staged at 2.7 km/s inertial.
At what velocities do the Falcon 9 and Electron stage? (Both of them are 2 stage, LOX, RP-1, also.)
Proceeds from the financing will be used to advance ABL's development and test program, including a planned integrated stage test in the second half of 2019. ABL is planning a first launch of RS1 in 2020.