Elon Musk and his companies are master in unveiling and announcing visions but not in delivering. I wonder if there is a special word for that in marketing... let's see if they will make it till 2023... wish them luck though.
When they announced their vertical landing program, critics across the industry laughed at them. Only a couple years later, their landings are so routine they don't even warrant press anymore.
Vertical landing a post-orbit rocket onto a floating barge is not a parlor trick. The DC-X never did that. And vertical landing for real commercial orbital flights—then reusing those rockets for more real commercial orbital flights—is orders of magnitude more impressive again.
If you want to land you need a bigger rocket for the same payload. But with how expensive rockets are, building them bigger and reusing them seems cheaper than letting them burn up. (And after a splashdown in saltwater refurbishment is way too expensive, so parachutes don't work well for reusability)
Off of the top of my head, with parachute landing you add mass because both:
- the large parachutes are quite heavy themselves as above (add some overhead for covers and support installation; I can't find any numbers)
- needs increased structural integrity to handle the tug during deployment and the much faster touch-down on landing; with propulsive landing you can essentially touchdown at 0/0/0 vertical/horizontal/angular velocities, as soon as you nail down the math of flight characteristics and engine control
- possibly some sort of reaction control, to achieve proper deployment attitude
- probably a smaller drogue chute(s) to handle supersonic flight, with all the complexity it adds
Moreover, using chutes:
- completely prevents RTL flights
- complicates abort modes; you'd need to dump fuel and oxidizer quick (without mixing and igniting, good luck) to be able to rely on the chutes alone.
However I guess the overriding concern for Musk was quick turn-around. With a parachute landing you have less control over the touchdown point [3]; the logistics of recovery, refurbishment and relaunch become much more involved, possibly spanning an ocean [4]. And with longer turn-around you need more flight hardware, and more ground support, to handle given amount of orbital or surface-to-surface traffic. Call it reducing the capex by going for somewhat costlier option that ensures much higher flight hardware utilization.
Lastly, using parachutes would create an image of low reliability; it's not something we would consider as to be routinely performed by commercial passenger flights. You don't want to ship passengers to "somewhere near your destination"; you want to deliver them to the airport, right next to the jet bridge (call it rocket bridge?) and promptly usher them to the passenger terminal.
Yes, yes, the routine BFR passenger travel is coming.
[1] https://en.wikipedia.org/wiki/Space_Shuttle_Solid_Rocket_Boo...
[2] http://www.spaceflight101.net/falcon-9-v11.html
[3] Gemini-style Rogalo wing would help, if it could be scaled. See https://i.pinimg.com/564x/b0/84/87/b08487e18f16402e4867981ff... and https://vintagespace.files.wordpress.com/2011/12/rogallo-win... Not as preposterous as it may seem, given that Buran's side-boosters were to glide to landing on deployable wings; see http://www.buran.ru/images/jpg/gk175-5.jpg
[4] you could bulk up the 1st stage enough to let it coast suborbitally all the way around globe to RTL, but that's another matter - and again uses up valuable fuel, and you run up against the rocket equation pretty quickly.
SpaceX tried it too, but had significant problems even re-entering without the rocket ripping apart, not even getting to the problems of recovering and refurbishing salt-water damaged hardware.
This kind of attitude might have made more sense before SpaceX had demonstrated it was possible. After showing how the technology can be further refined for full and rapid reuse, and landing on Mars, it just reads as ignorant or intentionally misleading.
2. Turnover of 24 hours would become impossible.
3. Structural stress so 10 re-flights would become unlikely.
Yeah what are they doing for space exploration anyway?
Tesla is not only selling the Model S and X for many years, and has with the Model 3 in the meantime the best-selling electrical car in the US.
So how are they not delivering?
As rocket science is.. rocket science, I do expect delays on the schedule. Especially safety concerns can easily make a development schedule slip. Yet, the SpaceX schedule slips seem to be small compared to other space ventures. The production of the first BFS prototype is under way, we are going to see the first test hops next year.
(If you wanted something that was a bit more polished, you could say "Promise the stars, deliver the moon." or as a complete sentence, "They promised the stars, then delivered the moon.")
-Signed someone with a day one Model 3 reservation still waiting for the 35K version.
wikipedia: https://en.wikipedia.org/wiki/Vaporware
And the OP replied to clarify, so I think vaporware is an unfair characterization. But I think that regardless, to be clear.
Maybe people have wrong expectations from working in software. SLS has a longer development time with a more tried-and-true design, and yet their deadlines slip as bad as those of SpaceX
Snakeoil?