Let's Do Some Rocket Math

Watch TIME's Exclusive Footage of NASA's Most Powerful Rocket Ever Under Construction, Time

Time's Jeffrey Kluger says "A rocket this big does not come cheap. Developing both the SLS and the ground systems that will support it will cost $11.5 billion, NASA says. And this is for a rocket that, unlike the space shuttle or the reusable boosters built by SpaceX, will be flown once and thrown away. According to a 2019 estimate by the Office of Management and Budget, the cost of building and flying a single SLS will reach $2 billion."

Keith's note: Well the NASA OIG just told us the other day that "In total, NASA has spent $37.2 billion to date on Artemis-related program activities." So Kluger's numbers are off by several hundred per cent. He cites OMB numbers - so maybe OIG numbers should be considered as well.

Kluger also says "NASA answers that while the private rockets may have muscle, they don't have as much as the SLS. The Falcon Heavy's liftoff thrust, for example, is 5 million pounds (2.25 kg). That makes a difference, since it may take two launches of a Falcon Heavy to lift as much payload as a single SLS, significantly cutting into any savings from a switchover to private rockets."

The advertised cost of a Falcon Heavy launch is $150 million. Let's just say that it would take two Falcon heavy's to launch something that only one SLS is required to launch i.e. a cost of $300 million. Kluger cites a $2 billion per launch cost of a SLS - so let's use that cost too. So - using only one Falcon Heavy would save $1.85 billion - but using two Falcon Heavy's would save taxpayers less, only $1.7 billion. Please tell me what is wrong with ONLY saving $1.7 billion per launch by using Falcon Heavy's instead of a SLS? Is this not a "significant" savings? Saved money is money that can be used for other things.

Using more math, at 2 Falcon Heavys = 1 SLS, this means that with the $1.7 billion saved by using Falcons instead of SLS, you save enough to launch an additional 5.6 SLS equivalents of upmass. All told for the launch of one SLS at $2 billion you can launch the equivalent upmass, using Falcon Heavy's, of 5.6 SLS launches.

Just sayin'

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This page contains a single entry by Keith Cowing published on April 22, 2021 4:43 PM.

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