Notes on fabrication of spacecraft

Speculation alert still applies:

Calculation for volume of the NTR rocket casing in the configuration outlined in the most recent post in the series.

Given that:

there's 1 million cc in cubic meter, and

liquid density of hydrogen at boiling point is 0.07099 g·cm−3, this gives

70990 g hydrogen per cubic meter, or

70.99 kg hydrogen per cubic meter.

We'll need 288.1 cubic meters volume to contain the H2 for NTR rocket based upon 45k pounds LH2 per Dewar's model.   Will it will fit inside of X-33 aeroshell?

X-33 is 21.2 meters long, 23.7 meters wide

Let's propose a rectangular tank 20 meters long by sqrt 15 or
3.87 square base by 20 meters long.  Since 3.87 meters times 3.25 feet in a meter, we know that the X-33 aeroshell will have to be at least 12.58 feet thick.  Since the tank fits inside of the X-33, then the X-33 aeroshell will have to be at least this thick.

How much volume in the aeroshell?

Given the formula for the area of triangle 1/2 b*h, so for the X-33
.5*23.7*21.2 equals 251.22 sq meter times 3.87 meters above gives approx 4, so an estimate for volume here of the X-33 aeroshell --- 1000 cubic meters.

So, a less than 300 cubic meter tank to fit inside 1000 cubic meter volume.  Looks good so far.

I figure it will fit down the center of the X-33.  The nose cap can lift up to allow the now cylindrical rocket stack to exit at the Karman line.  The nose cap then comes down and the X-33 flies back to base.

The X-37C/NTR rocket stack massing at 91k lbs can fly up towards orbit.

Update:

Oops!!!

Forgot about the X-37C itself.  It is nearly 30 feet long in its current X-37B configuration.  It will get bigger when/if it is upgraded to an X-37C.

That means it won't fit in the X-33 aeroshell.  It looks like nearly all of it will have to be mounted outside of the aeroshell.

Even so, the complete package still is shorter than the Space Shuttle which rode atop the 747.

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