Pardon me if this has already been discussed. However, I would be interested to know how Soyuz scores based on the same criteria.
It's your friendly ASAP sticking their nose in again Interesting, all the same. Used some Nathan L2 renders, of course, to make the article sexier.https://www.nasaspaceflight.com/2017/08/asap-concerns-commercial-crew-loc-risks/
The ASAP was presented with the three main “programmatic and safety risks” currently challenging the CCP, noted as the:A. “inability to meet Loss of Crew (LOC) metricsB. DoD’s Search and Rescue posture and capabilityC. the possibility of aborts taking place in sea states that would be unsafe for rescue.”
That was acknowledged by another ASAP panel member, who noted “One of the things the Panel has begun to observe and discuss is the considerable statistical distribution between the probabilities that are used in the model. As an example, one of the current calculations uses a value of 1:300 as a calculation for overall risk, but statistically, that number can vary between 1:140 and 1:1200.”
As for the sea state concern during ascent, how much more difficult would this be than having theneed to a trans-atlantic abort site during the shuttle era?
Rephrasing the point, how much would beprobability of meeting launch commit criteria be lowered if the sea state was added to the ratherlarge list of constraints that already exists.
Quote from: duh on 08/23/2017 08:11 pmAs for the sea state concern during ascent, how much more difficult would this be than having theneed to a trans-atlantic abort site during the shuttle era?A TAL site has only a few people, a ship in the Atlantic has many times moreQuote from: duh on 08/23/2017 08:11 pm Rephrasing the point, how much would beprobability of meeting launch commit criteria be lowered if the sea state was added to the ratherlarge list of constraints that already exists.It already is for the barge and it was also for other manned capsule missions.
Sea state can effect re-entry. Although if the capsule can wait an extra 45 minutes it can fly from the Pacific to the Atlantic.
Quote from: ElGuapoGuano1 on 08/23/2017 04:26 pmPardon me if this has already been discussed. However, I would be interested to know how Soyuz scores based on the same criteria.I found a brief mention in the 2005 ESAShttps://www.nasa.gov/pdf/140639main_ESAS_08.pdfWhich gives the Soyuz LOC risk as 0.3%, or 1 in 333, and 0.5%, or 1 in 200, but these numbers are in a comparative chart, it does not explain how they arrived at the risk numbers.
So what happened to all the "hand-wringing" over SpaceX planning to fuel the F9 while the astronauts are on board? I am just surprised considering all the back and forth about this proposed practice after the AMOS-6 anomaly that the article makes no mention of it being a current concern for ASAP.
No idea: But STS had 1 in 50, so 2%. Seems NASA wS OK with that.
The article is saying the LOC is higher for on-orbit than during launch landing. That seems counter intuitive to me. The huge ISS has been up there for nearly 19 years without taking any major hits for debris. Historically, LOC has occurred during launch and entry.
All this had wringing would magically go away if Orion/SLS was the only US system of choice available to fly to ISS...
...it was all kinda arbitrary to begin with in my opinion.