In article om,
says...

Questions:


1-If both boosters separate at same time, what sort of logistics are
involved in landing them, presumably at same time?

two barges a few km apart ? 2 landing pads on ground ? (at what distance?)

Nope, two separate landing pads at Cape Canaveral. The boosters
separate fairly early compared to the Falcon 9 first stage, so they'll
have enough leftover fuel to return to the cape safely.

Apart from extra-terrestrial missions, what sort of commercial payloads
*need* this?

All payloads so far where the Falcon 9 first stage was deliberately
expended. This has been due to heavy satellites headed to
geosynchronous orbits.

Or is this about launching multiple satellites at the same time?

Possibly, but this is often difficult to arrange, since both satellites
have to be headed roughly to the same orbit.

Note that Heavy still doesn't have a "high energy" upper stage. It's
essentially got the Falcon 9 upper stage. So even though the LEO
payload of Heavy is quite impressive, the geosynchronous transfer orbit
payload isn't as impressive as you'd think.

The key about Heavy is that they'll recover and reuse both the boosters
and the core (first) stage. So 27 out of 28 engines and 3/4 of the
stages. This will reduce costs, even if the payloads aren't anywhere
near its maximum (mass) capacity. Remember, you have to sacrifice
payload capacity to reserve fuel to return those 3 out of 4 stages.

Jeff
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