# I can jog at Mach I? **URL:** \ **Category:** Factual Questions\ **Created:** [May 25, 2003, 2:25am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331 "2003-05-25T02:25:53Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![El\_Cid\_Viscoso](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@El\_Cid\_Viscoso](https://boards.straightdope.com/u/El_Cid_Viscoso)\ **Post date:** [May 25, 2003, 2:25am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/1 "2003-05-25T02:25:53Z")
So let’s say I’m flying in a plane, traveling at 655 miles per hour at an altitude of 20,000 feet. I can easily jog at 6 miles per hour. The plane is traveling at 655MPH, and I’ve just broken the sound barrier? Is there a boom? If so, is it smaller, maybe fart-like? Cecil won’t answer my calls. ---
**Author:** ![Marley23](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Marley23](https://boards.straightdope.com/u/Marley23)\ **Post date:** [May 25, 2003, 2:28am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/2 "2003-05-25T02:28:25Z")
Probably not, since you’re only moving six miles an hour relative to the air in the plane. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [May 25, 2003, 2:28am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/3 "2003-05-25T02:28:51Z")
This thread will be locked, and of course you will rightfully and properly punished in the House of Pain, but this did make me laugh more than anything else I’ve read all day. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [May 25, 2003, 2:30am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/4 "2003-05-25T02:30:34Z")
No. You are travelling faster than sound relative to the Earth, but _not_ relative to the air around you. A sonic boom is caused by an object moving through a medium faster than the speed of sound through it. ---
**Author:** ![El\_Cid\_Viscoso](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@El\_Cid\_Viscoso](https://boards.straightdope.com/u/El_Cid_Viscoso)\ **Post date:** [May 25, 2003, 2:30am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/5 "2003-05-25T02:30:45Z")
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**Author:** ![Flying\_Monk](https://avatars.discourse-cdn.com/v4/letter/f/48db29/32.png) [@Flying\_Monk](https://boards.straightdope.com/u/Flying_Monk)\ **Post date:** [May 25, 2003, 11:04am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/6 "2003-05-25T11:04:46Z")
Boy, this thread reminds me of the time I was travelling at the speed of light in my car/spaceship and I turned on the headlights… ---
**Author:** ![Mr\_Sherbet](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mr\_Sherbet](https://boards.straightdope.com/u/Mr_Sherbet)\ **Post date:** [May 25, 2003, 11:16am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/7 "2003-05-25T11:16:43Z")
and then there was the time i went back in time and shot my grandfather. Talk about the universe collapsing! ---
**Author:** ![Achernar](https://avatars.discourse-cdn.com/v4/letter/a/e274bd/32.png) [@Achernar](https://boards.straightdope.com/u/Achernar)\ **Post date:** [May 25, 2003, 11:23am UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/8 "2003-05-25T11:23:10Z")
> [@](#): > > \*Originally posted by Q.E.D. \* > No. You are travelling faster than sound relative to the Earth… Is that even true? I thought sound speed was greater than 661 MPH. [This calculator](http://www.grc.nasa.gov/WWW/K-12/airplane/sound.html) suggests Mach 1 = 707 MPH at 20,000 feet. ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [May 25, 2003, 12:08pm UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/9 "2003-05-25T12:08:23Z")
“Yike. What the heck was that?” “Just a sonic fart. **Mr.B** likes to jog in his plane about this time every morning. You’ll get used to it.” ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [May 25, 2003, 2:23pm UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/10 "2003-05-25T14:23:26Z")
Also remember that you are traveling quite fast as the earth rotates (unless you are on/near one of the poles) and aslo moving at a good speed as the earth moves round the sun, and as the sun travels around the Milky Way. ---
**Author:** ![Keeve](https://avatars.discourse-cdn.com/v4/letter/k/f07891/32.png) [@Keeve](https://boards.straightdope.com/u/Keeve)\ **Post date:** [May 25, 2003, 4:56pm UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/11 "2003-05-25T16:56:25Z")
> [@](#): > > _Originally posted by Mr. B in the OP_ > **So let’s say I’m flying in a plane… I can easily jog at 6 miles per hour.** In those narrow aisles? Without bumping into a coffee cart or a passenger’s elbow? _Good luck!_ ---
**Author:** ![Keeve](https://avatars.discourse-cdn.com/v4/letter/k/f07891/32.png) [@Keeve](https://boards.straightdope.com/u/Keeve)\ **Post date:** [May 25, 2003, 4:57pm UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/12 "2003-05-25T16:57:51Z")
> [@](#): > > _Originally posted by Mr. B in the OP_ > **So let’s say I’m flying in a plane,** Oh, sorry, I missed that. You’re _flying_ in the plane, not jogging. Well, watch out for the movie screen, ok? ---
**Author:** ![Shade](https://avatars.discourse-cdn.com/v4/letter/s/2bfe46/32.png) [@Shade](https://boards.straightdope.com/u/Shade)\ **Post date:** [May 25, 2003, 6:37pm UTC](https://boards.straightdope.com/t/i-can-jog-at-mach-i/177331/13 "2003-05-25T18:37:25Z")
Which were you asking? (a) If you’re inside a closed (ish) plane, then the air’s going at the same speed you are, so if you start running… never mind, what everyone else said. (b) If you’re on a wing or something, then running at 6mph (assuming the plane is at 3mph below, whatever that speed would be) would presumably make a boom. Of course, you probably wouldn’t be able to stand still let alone run forward as there’s a near mach-1 wind in your face. This would be much the same as if here was a wind of the speed of the plane blowing past you on the ground.