This is a series, I on the world. I'm John Bachelor. Behind the Black, Bob Zimmerman joins to help us understand the drama of Starliner. Starliner is built by Boeing and it's

right now attached to the ISS. Those things are completely firm. After that, Bob, a very good evening to you.

Starliner is still at the ISS and the two astronauts who went up with it are still on ISS.

That's as far as I know.

What comes next?

Good evening.

Well, John, you might also know as much,

I might know as much as you do,

but we have some information.

Up to the last like six weeks they've been doing tests to try to determine

exactly why some thrusters did not function properly during the docking of this man capsule

built by Boeing with two astronauts on board did not fire properly during docking. And as of two weeks ago in the previous briefing, the Boeing

and Nasser engineers said they think they determined the problem based on both a hot fire test on

I assess of these thrusters as well as duplicate testing done on the ground and

they thought I had to do with a Teflon seal in the thruster that when the

trust to get hot expands and ends up blocking the flow of fuel to the thruster and that's why it gets blocked.

And they thought they had everything right and so they said we're going to do some additional

hot fire tests on I assess with those

thrusters to confirm what we have found on the ground and it appears now based on a

briefing today that the trust design on ISS on small liner didn't behave as

expected in fact they worked great they worked absolutely great they showed no

indication of that that's long field expanding and blocking flow.

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