5 ms·
Correct, the engines were going to be retired anyway but they are keen to reuse the titanium grid fins on the boosters which cost a small fortune to make. The
by Laforet 9y ago
Correct, the engines were going to be retired anyway but they are keen to reuse the titanium grid fins on the boosters which cost a small fortune to make.
The core actually had older ablative grid fins made of aluminium so no great loss there[0].
[0]https://i.redd.it/l6s2bds7pl801.png https://i.redd.it/l6s2bds7pl801.png
- gameswithgo 9y agoahh, I noticed that in the feed and was wondering why. I guess they expected it was the least likely to work? or needed the better grid fins less because of the cylindrical top
- josu 9y agoCan they still recover them?
- 0xTJ 9y agoHave you seen an approximate price for those fins anywhere. I saw the interviews, but I want to know how expensive is expensive.
- nigwil_ 9y agoPlatinum is USD$32K per KG, so if the platinum grid fins are 100KG, then they would cost > $300K each just for materials. With 4 per booster that might be a million dollar price tag for the grid fins.
- varjag 9y agoThe fins are titanium, not platinum. The cost of material is negligible.
- nigwil_ 9y agoOops, you’re right my mistake
- aquadrop 9y agoThat would be $3200k for each, but they are made out of titanium, not platinum, and most of the cost is in the work, not material. I'd like to know the price too though.
- philjohn 9y agoYep - Titanium is notoriously difficult to work with.
- TomK32 9y agoSo difficult that the SR-71 leaked fuel before starts and had to be re-fueled right after take-off. https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Fuel https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Fuel
- jpitz 9y agoThe Blackbirds leaked because they had engineered gaps to allow for heat expansion.
- wand3r 9y agoI bet SpaceX could engineer something in spec that wouldn't leak fuel or need to be immediately refueled though.
- oceanswave 9y agoAnd we’re also comparing an aircraft designed in the late 1950’s and built in the early 60’s by slide rule (while still being extremely accurate) to modern spacecraft having the benefit of decades of materials and design technology
- votingprawn 9y agoThe SR-71 took off with a small fuel load to reduce stress and improve engine-out performance, that is why it was refuelled immediately after take-off. The mental image of it leaking so much fuel on the ground such that it needed immediate refuelling is a myth propagated extensively on the internet.
- epanchin 9y agoKU Leuven states the grid fins at 41kg. (The same volume of material would be 193kg in platinum)