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>><<SNIP from MSNBC >>
>>That is the point from which the Sea Launch joint venture plans to propel
>>a three-stage, Russian- and Ukrainian-built Zenit 3SL rocket into space. On
>>board will be a 10,000-pound "dummy" payload built to resemble the
>>commercial telecommunications satellites that Sea Launch hopes to routinely
>>ferry into orbit. 

>Why is P3D not on board?

>Was Boeing approached/asked if we could tag along onboard?

I cannot speak with any certainty about whether or not Boeing was
asked about carrying P3D. If there were any discussions they would
have been of a politically sensitive nature and could not be 
disclosed to the outside world (including us members). However 
I can review some of the issues that would be involved in planning 
such a launch. 

To demonstrate the capability of the launch vehicle to handle their
prospective customer's payloads, Boeing would have wanted a test 
satellite that would closely match the size, mass, and center of 
gravity of a large commercial satellite in order to gain the 
confidence of prospective commercial clients. Phase 3D would have 
been too small to be a representative "dummy" satellite to stand 
in for a large commercial satellite. It might have been possible
to design a dummy satellite to fit on top of P3D, but such an effort
would have had to start at least a year before launch. 

The Specific Bearing Structure (SBS) which carries P3D was designed
with a certain diameter to fit on top of the Ariane upper stage.
You may recall that Amsat had to scrap the initial "Falcon" satellite
design and start over again when Ariane decided to change the bolt 
hole pattern on top of the upper stage. Moving the satellite to 
another launch vehicle might require a similar redesign unless we
were very lucky. 

For just one example of the hoops you have to jump through to get on 
a launch vehicle, consider that in order to separate the satellite 
from its launch vehicle, you need some kind of pyrotechnic circuit 
wired to your explosive bolts and interfaced with the vehicle's event 
sequencer. Although you or I could probably design and build such a 
circuit in one weekend, the commercial aerospace world does not work 
that way. Even a "simple" pyro circuit takes massive amounts of 
paperwork and design reviews before it would be accepted for flight 
on a multi-million dollar rocket. The corporate world just doesn't 
work the way we do. You have to prove beyond an unreasonable doubt 
that your pyro circuit won't fire the separation bolts too early 
and blow up the whole stack during liftoff. That would not be the 
impression that Boeing wants to show its potential customers. You 
have to convince their engineers and managers that your satellite 
won't fall to pieces under launch vibration or leak its toxic and 
explosive rocket fuel during the launch. You are asking them to 
assume a big risk of failure on their very expensive rocket, in 
return for little or no financial reward. Most sane launch managers 
would refuse such a deal. The fact that ESA's engineers accepted 
our design for flight on an Ariane means nothing to Boeing, they 
would want to review everything from the ground up, and they would 
have to pay their engineers for the time spent doing the review. 
You are asking for a pretty big favor when you ask them if we can 
"just tag along".

Boeing had probably hoped to launch a paying customer on the first 
Sealaunch, when that customer failed to materialize (because they all 
remember what happened on the maiden flight of Boeing's Delta 3), 
the decision to fly a dummy payload was probably made at the last 
minute. There would not have been time for Boeing's engineers to 
review our design data for flight acceptance. This was the same 
problem that kept us from flying on Ariane 503 when their customer 
dropped out at the last minute. 

Even for a small 10 kg microsatellite, there are many issues 
involved in placing your secondary payload on top of a rocket. 
For a 600 kg satellite with a live propulsion system, the issues 
are even greater. 

The bottom line is that Phase 3D and the SBS structure that carries
it were designed to fly on an Ariane, and Ariane is still the best
hope that we have for a launch without an extensive and time consuming
redesign effort. 

>Or perhaps another, lesser-valued amateur satellite that we could 
>afford to risk on an unproven launch vehicle?

As Bob Bruninga pointed out, there was an attempt to build a quick
reaction ham payload on the Sealaunch test article, which might have 
been successful but for a last minute rejection by the export licensing
authorities, who had granted approval for an inert dummy but not 
for a satellite with onboard electronic systems. 

>But since P3D was to fly on an Ariane(sp?)5, would not the paperwork
>already be in order?

For an export to France maybe. Exporting it to Russia would be a
whole different can of worms. 

Dan Schultz N8FGV
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