From: jamesoberg@aol.com (JamesOberg)
Newsgroups: sci.space.history
Subject: Re: Mercury (Friendship 7) orbit inclination Q
Date: 1 Jul 1998 20:38:11 GMT

<<I was checking out NASA's Mercury/Shuttle comparison page
(http://shuttle.nasa.gov/index.html/mershut.html) and there's an
entry in there that says Glenn's craft was launched into an orbit
with a 32.54 degree inclination.  The question is, why, or more
specifically, why wasn't it launched directly east (as the Shuttle
carrying Glenn will be) for a 28.45 degree inclination?>>

There's a clever orbital mechanics reason for this. The slightly higher
inclination puts the spacecraft into the same recovery zone after 3 revs as it
would be for an abort during launch -- hence, only one recovery fleet needed.

If you launched into 28 degrees, you'd be at the northerly point at launch, and
every rev later you'd be 22.5 degrees further west before heading south --
you'd pass far south of the recovery ships stationed to support launch abort.