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From: gherbert@crl.com (George Herbert)
Newsgroups: sci.space.policy
Subject: Re: landings (was Re: MSFC engine)
Date: 7 Mar 1996 23:15:25 -0800

In article <4hlnp0$ot2@news.microsoft.com>,
Edward V. Wright <edwright@microsoft.com> wrote:
>[...]
>A few years ago, the United States Navy decided it needed a deep-submergence 
>vehicle to rescue crew members from crashed submarines. So, they hired an 
>aerospace contractor (Lockheed) to build them one. It cost $100 million.
>At the same time, the Royal Navy decided it needed the same capability,
>but it didn't hae $110 million to invest in a new vehicle. So it made a
>deal with an offshore oil company. The oil company would purchase a 
>submersible capable of being used for offshore oil operations *and* 
>submarine rescue missions. The Royal Navy would lease the submersible
>for part of the year and have the right to commandeer it any time in
>case of an emergency. This vehicle, which needed to perform not one but
>two missions, was designed and built for $750,000. 

It is worthwhile noting some other differences in these two craft.
* DSRV (Deep Submergence Rescue Vehicle, the Locheed/Navy one) had to
  carry about three times as many people at once as the British one.
  The US has more crew on its subs, which are bigger than the British
  submarines are. 
* The US also operates its submarines regularly at just about every
  location around the globe which has enough water, which means
  that we could have a sub down emergency *anywhere*, not just in the north
  atlantic near where the oil companies are drilling.
* We also have more submarines (about 8 times more, if I remember right).
* That mandates more units (there are three DSRV vehicles).
* That mandates more capable units.
* That mandates units which can be air-delivered to anywhere around the
  globe (DSRV fits on a C-5A).

In short, instead of a modified off the shelf vehicle (which cost more than
$750k, btw, it was more than 750,000 british *pounds* when it was ordered,
and it inflated...), Locheed had to build three completely custom,
large, highly capable, high endurance, air transportable large minisubs.
If the size was a factor of 3 cost increase, the capabilities and endurance
a factor of two each, and the air transportability a factor of two,
then the three subs should have cost about $72 million instead of the
roughly $1m for the british vehicle.  The $111 or so million they ended
up costing is higher than a trivial ROM scaling law suggests, but within
reason.  

This is an excellent example of comparing apples and oranges, once you
look hard enough.

Sometimes it pays to have a Naval Architecture background 8-)


-george william herbert
Retro Aerospace
gherbert@crl.com


From: gherbert@crl.com (George Herbert)
Newsgroups: sci.space.policy
Subject: Re: landings (was Re: MSFC engine)
Date: 8 Mar 1996 12:37:47 -0800

In article <4hpe9o$rdb@news.cc.ucf.edu>,
Thomas Clarke <clarke@acme.ist.ucf.edu> wrote:
>gherbert@crl.com (George Herbert) writes:
>> It is worthwhile noting some other differences in these two craft.
>> * DSRV had to carry about three times as many ... as the British one.
>> * (operational factors) mandates more units (there are three DSRV vehicles).
>> * ... and  units which can be air-delivered to anywhere around the
>>   globe (DSRV fits on a C-5A).
>
>Still sounds like the Navy didn't get a good deal to me.
>Nine times $750K ~ $7 mil << $110 mil the Navy paid.
>It would be cheaper to buy nine smaller British style rescue vehicles,
>that to develop the three larger ones.  

Operational constraints.  Have to be able to evacuate the people within
a specified time, and docking/undocking are a noticable chunk of that time.
Not to mention that making them airliftable meant that they had to use
titanium pressure hulls instead of steel, the DSRV is about twice as 
fast and twice as long endurance, has onboard sensors to *find* 
the missing sub, ... 

This was a very shallow comparason of very different vehicles with 
very different missions.  The origional comparason missed many technical
and operational constraints that differ, and offers no insight whatsoever
into government versus civilian procurement, except that in this case
the government's mission specifications and requirements were several
orders of magnitude more difficult than those for a slighly modified
civilian dive support sub.

There are plenty of examples from Aerospace industries of the sorts
of things which you are trying to demonstrate.  Things like the 18-volume,
15,000 page Atlas procurement docs set for a NASA launch versus the
125 page specs and contract for a commercial launch of the same model
rocket.  Looking outside aerospace and picking particularly bad
examples and making inaccurate comparasons are not instructive.
You may be offended that the US Navy bought a set of airliftable,
high-tech, titanium minisubs for $110 million, but they had good
reasons to do so and the problem they were solving was nontrivial.
Comparason with trivial modifications to a commercial sub which
could not possibly have met any of the US Navy requirements is
technically shallow.


-george william herbert
Retro Aerospace
gherbert@crl.com

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