Bob and Doug make safe return to earth, Percy’s silence scares mission control

Published 8:00 am Saturday, August 8, 2020

It was relief to see the Dragon capsule returned to earth in such good shape.

Elon Musk has done it again. Doug Hurley and Bob Behnken are safely home.
I spent a chunk of last Sunday afternoon watching them come in and land under their four parachutes in a calm Gulf of Mexico.

I was determined to watch until they came out of the capsule.

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It took over an hour from the time it was on board the ship “the Navigator” to exit the capsule.
The problem was the leftover rocket fuel, nitrogen tetroxide, it is a fuel, when mixed with a hydrazine, burns spontaneously.

They call it hypergolic. It has the advantage of being able to be stored a long time as stable liquids. It was used to lift off the Apollo landers from the moon.

Since the fuel spontaneously ignites when mixed, there is no problem with igniting it or shutting down systems for restarts.

Anyway, the problem Sunday was the extra, very toxic, nitrogen tetroxide had to be purged away from the capsule before Doug and Bob could come out.

It is comforting to be able to use our own rockets to take astronauts into space.

I would rather see our money go to Elon Musk and company rather than to Russia. NASA has paid out $3.37 billion over the 12 years. The price in 2018 was $81 million per seat for a round trip.

SpaceX has fired off a new rocket using methane and oxygen for fuel.

They did a short hop and then recovered the rocket intact by controlling the return to a nearby pad.

They also had other successes. They reused the booster that was used to send the astronauts to the International Space Station to send up a satellite for Korea. They not only recovered the booster again, but also the fairing on the nose cone that were jettisoned as the rocket left the earth atmosphere.

They used large nets from two ships they had stationed under the expected landing point of the fairing and caught both of them for the first time. Elon has a talent for hiring talented people for carrying out his ideas and no doubt coming up with ideas themselves. This was the 90th flight of their Falcon 9 rocket, all successful.

This is an update of Perseverance, who I have named Percy since it is easier to spell.

It gave the ground controllers a bit of a scare. As the Atlas launched it into an earth orbit altitude, they lost communication.

There were two explanations — the radio signal was so strong it overwhelmed the ground radios or it went into earth’s shadow and cooled it too much.

Anyway, when a $2.87 billion is at stake, it causes a great deal of concern.

The communication was restored and the hope for no more problems until the prelude to landing.

They call it “seven minutes of terror” as they have programmed it to land by “sky crane” as was how the last rover landed. We will find out in February 2021 if it was successful.

Don Lee, a pilot flying out of Lawrence County Airport since 1970, has been in charge of equipment and grounds maintenance for the last several years. He can be reached at eelnod22@gmail.com