So for fairing reuse, what are the problems? How do they limit ( or eliminate ) the possible solutions?
All this "fairing reuse" talk seems to be misleading. You don't want that. What you actually want - but somehow refuse to call it - is a payload bay with doors that can open and close. (like on Shuttle) It's a certainly doable and a good idea for a reusable upper stage, but it will weigh significantly more and be a lot more complex. You need a lot of mass margin to pull it off. (An upper stage with an integrated cargo bay is what I have been advocating for commercial BFR use, where margins would be plentiful)But don't think of it is a "reused fairing". Think of it as a payload bay - it is a far more realistic approach.
This is how fast a fairing comes off
Not sure if this is feasible or buys you anything much, but one could envision a system where separated sides fairing will remain connected via a tether. Definitely would require extra pyrotechnics to make the separation clean - and separation is risky as it is.
snip...#1 Orientation is paramount, going convex first you can spread conveniently the shock wave at the atmospheric interface, then going concave first when subsonic you can slow down under 20 m/s of terminal velocity. I see deployable panels for convex first, and midsize drogues/parachutes for concave first.#3 Radio beacons snip...
Quote from: cambrianera on 04/04/2016 08:06 pmsnip...#1 Orientation is paramount, going convex first you can spread conveniently the shock wave at the atmospheric interface, then going concave first when subsonic you can slow down under 20 m/s of terminal velocity. I see deployable panels for convex first, and midsize drogues/parachutes for concave first.#3 Radio beacons snip...As to radio beacons, I think that not only could the fairings be instrumented with either radio beacons, but also sono emitters that could be picked up and triangulated with prepositioned sonobouys in the landing zone. The tough part is still getting to a landing zone.
When the fairing is jettisoned, a COPV attached inside the fairing half will inflate the bladder, and the pressure of the gas will peel the bladder away from the inside of the fairing
Quote from: Stan-1967 on 04/05/2016 06:01 amWhen the fairing is jettisoned, a COPV attached inside the fairing half will inflate the bladder, and the pressure of the gas will peel the bladder away from the inside of the fairing How are you going to keep it in place and yet make inflation "peel" it off.
But seriously, to what effect would the tether do anything useful? What benefit is derived from this? What do you want to do with two fairing halves connected with a tether?
Quote from: Stan-1967 on 04/05/2016 04:58 amBut seriously, to what effect would the tether do anything useful? What benefit is derived from this? What do you want to do with two fairing halves connected with a tether?You could have the tether reel in a few seconds after clean separation, pulling the sides together. This might make the reentry tumble more survivable, or worse. No idea - just an idle thought
I had another idea for stability. Imagine the inside of each fairing to have a bladder ( thin rubber/plastic/composite?) lightly adhered ( think 3M yellow stick notes type of adhesion) to the inside surface of the composite fairing shell. All the anechoic foams,insulation, & active sonic devices are layered on top of this bladder, and continue to perform the functions needed for the fairing environment. The fairing can look and work just as the existing items currently do. When the fairing is jettisoned, a COPV attached inside the fairing half will inflate the bladder, and the pressure of the gas will peel the bladder away from the inside of the fairing and inflate to a form that mirrors the composite fairing half, and once inflated the fairing will have virtually the same shape as a full fairing. Most of the anechoic foams/insulation will pop off during this event.
-risk of tangling into payload (or between tethers, if more than one);