Re: VTVL?

In article <46AE2177.3090306@xxxxxxxxxxx>,
"Wayne C. Gramlich" <Gramlich@xxxxxxxxxxx> wrote:

If you arrange your launch site such that the recovery site
is in the ocean, the range of possible recovery sites becomes
much larger. In addition, you have the option of floating
the first stage back to land rather thay flying it back.
Floating the first stage back would take longer than flying
it back, and would cut down on flight rate. However, you
also have the option of flying the smallish, but more expensive
rocket engine back to the launch site and just floating the
big bulky first stage tank back to land. This would require
multiple first stage tanks to sustain a rapid flight rate.
It might be an acceptable business/engineering trade-off.

Irrespective of whether the recovery site is on land or on
ocean, the weather at both launch and reentry site must be
acceptable. This will also adversely influence flight rate.

Dropping almost anything into seawater and soaking it there awhile is
not a recipe for long reliable life, at least not without additional
repair and refurbishment work. SpaceX says it plans sea recovery of
their first stages to avoid the additional development work of flyback
and landing. We'll see how well it works in practice.
.