NASA Reduced Gravity Research Program


NASA’s C9B is flying again today. Check out the zero-g maneuver at 11:20.


Is this the “Vomit Comet”? They used to use a 707 for that. This appears to be a DC-9…

Your link will show whatever flight is current when someone clicks on it. If someone clicks on it in three months, they’ll see a flight from August 2007 and the reference to 11:20 will not apply to that flight.
will always link to that particular flight.


thanks for the tip


Don’t forget to mention the time zone. The flight’s log shows the big dive at 8:20 when I look at it because I’m in the Pacific time zone.


Info here: … story.html


Glad to help, and welcome to the forum!

Heck! I didn’t even realize this until you mentioned it.


So, does this vehicle replace the 707 as the “Vomit Comet” to train astronauts for zero-G environment, or is this in addition to the old 707 and used for other zero-G missions? The 9’s cabin is considerably smaller than a 707, so I would think if they were gonna replace the 707, then a 757 would be a more likely candidate for the job.


i believe this is a replacement for the 707/kc135a, which was retired.


Another Vomit Comet type flight out of Chicago (ORD) yesterday @ 16:15. This one was a 727 charter type flight discussed on the radio this morning by one of the hosts who was on the flight.


Welcome to the forums, willlds!

Here’s a little tip for posting links to flights. The URL you quoted is the LIVE flight. When someone clicks on that link three months from now, they will see the data for whatever flight was flown last, which likely will not be the same flight you mention in this post.

If you look down at the list of previous flights and click on the date of the specific flight you want to refer to, it will bring up a URL that will permanently link to that specific link. Here is the permanent URL to that flight. … /KORD/KORD


From the track log, it looks more like an ordinary descent than a zero-g maneuver. In a zero G maneuver the vertical speed must approximately double every minute, because vertical speed is the derivative of height, which is -16t^2 in feet-second units; in other words, the airplane descends with the same profile as a rock, so objects inside do not accelerate realtive to the airplane.

I suspect that 0g stuff is done with a block altitude clearance, and I don’t think FlightAware handles these well.


That’s vertical distance traveled; the vertical speed is -32t ft/sec.


Isn’t it 32ft per second/per second