# Breaking the "sound barrier" without an engine **URL:** \ **Category:** Factual Questions\ **Created:** [November 3, 1999, 2:15pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529 "1999-11-03T14:15:00Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Ringo](https://avatars.discourse-cdn.com/v4/letter/r/779978/32.png) [@Ringo](https://boards.straightdope.com/u/Ringo)\ **Post date:** [November 4, 1999, 1:38am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/21 "1999-11-04T01:38:00Z")
From the thread **Strainger** linked: > [@](#): > > … according to my September 1999 issue of National Geographic, on August 16, 1960 U.S. Army Capt. Joe Kittinger jumped from a balloon at a still record altitude of 102,800 feet. According to the magazine he was in freefall for thirteen minutes and reached a speed of “more than 600 miles an hour,…” which, while not breaking the sound barrier, is close enough to say he approached it. That was my only factual contribution to the thread, but others contributed much intersting stuff, and the subject was pretty well covered. The freefall for 13 minutes cannot be correct, as is addressed in that thread. ---
**Author:** ![ellis555](https://avatars.discourse-cdn.com/v4/letter/e/e36b37/32.png) [@ellis555](https://boards.straightdope.com/u/ellis555)\ **Post date:** [November 4, 1999, 1:42am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/22 "1999-11-04T01:42:00Z")
to back up GasDr, check the issue of national geographic featuring the article on the first circumnavigation of the globe by balloon. this feat was mentioned in the same issue. -ellis ---
**Author:** ![Nickrz](https://avatars.discourse-cdn.com/v4/letter/n/bbce88/32.png) [@Nickrz](https://boards.straightdope.com/u/Nickrz)\ **Post date:** [November 4, 1999, 2:25am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/23 "1999-11-04T02:25:00Z")
That old thread left the question hanging - did the guy break the sound barrier or not? (I think a careful reread of member Omniscient’s post there says he did not). ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [November 4, 1999, 4:29am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/24 "1999-11-04T04:29:00Z")
The information I’ve read says that he did not. There’s a big difference between being just under the speed of sound and just over it. I don’t think a non-streamlined projectile like a human could do it without having a giant engine strapped to him. ---
**Author:** ![system](https://global.discourse-cdn.com/straightdope/original/2X/e/e489c3b7d8fce19c4b355dd4fc3f88cc39c34b87.png) [@system](https://boards.straightdope.com/u/system)\ **Post date:** [November 4, 1999, 6:22am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/25 "1999-11-04T06:22:00Z")
But if someone did manage to break the sound barrier while parachuting head first, wouldn’t he have then been capable of talking out of his ass? ---
**Author:** ![GasDr](https://avatars.discourse-cdn.com/v4/letter/g/ba9def/32.png) [@GasDr](https://boards.straightdope.com/u/GasDr)\ **Post date:** [November 4, 1999, 10:44pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/26 "1999-11-04T22:44:00Z")
HE BROKE THE SOUND BARRIER. There were a 3 or 4 people crazy enough to jump at this rediculously high altitude. ONE of these jumpers DID BREAK the sound barrier. ---
**Author:** ![Nickrz](https://avatars.discourse-cdn.com/v4/letter/n/bbce88/32.png) [@Nickrz](https://boards.straightdope.com/u/Nickrz)\ **Post date:** [November 4, 1999, 11:54pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/27 "1999-11-04T23:54:00Z")
Oh-oh. Dare I repeat it? Do you have cites for your contention, Dr? We’ve not seen any so far, and I would greatly like to see this question put to rest. ---
**Author:** ![Satan](https://avatars.discourse-cdn.com/v4/letter/s/e9bcb4/32.png) [@Satan](https://boards.straightdope.com/u/Satan)\ **Post date:** [November 4, 1999, 11:57pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/28 "1999-11-04T23:57:00Z")
Give us a site, GasDr. You are so adamant about this, but the only site on this site (from another site, I might add) says that a diver “approached” the speed of sound and did not break it. * * * Yer pal, Satan ---
**Author:** ![Satan](https://avatars.discourse-cdn.com/v4/letter/s/e9bcb4/32.png) [@Satan](https://boards.straightdope.com/u/Satan)\ **Post date:** [November 4, 1999, 11:58pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/29 "1999-11-04T23:58:00Z")
I love duplicity… * * * Yer pal, Satan ---
**Author:** ![Ringo](https://avatars.discourse-cdn.com/v4/letter/r/779978/32.png) [@Ringo](https://boards.straightdope.com/u/Ringo)\ **Post date:** [November 5, 1999, 12:11am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/30 "1999-11-05T00:11:00Z")
BTW, anyone here happen to know what the speed os sound is at, say, 80,000 feet? ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [November 5, 1999, 12:32am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/31 "1999-11-05T00:32:00Z")
Hmmn… Joe Kittinger’s home page lists among his accomplishments as "First man to exceed the sound barrier in free-fall (714 mph 16 August 1960 during record balloon jump). He jumped from 102,000 ft. This contradicts other information I’ve read. ---
**Author:** ![pluto](https://avatars.discourse-cdn.com/v4/letter/p/f08c70/32.png) [@pluto](https://boards.straightdope.com/u/pluto)\ **Post date:** [November 5, 1999, 12:47am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/32 "1999-11-05T00:47:00Z")
1. Kittinger did make the record high jump. I read a book describing high altitude balloon testing the Air Force did (partly) to prepare for manned flight. I will give you a reference as soon as I can get to the library. 2. He was wearing a pressure suit and he was testing a parachute intended to be safe at very high speed openings. The chute(s) opened in stages, first just a drag chute to get him oriented then a small one to slow him slightly and then the main chute. He had to free fall for a long time to get down to breathable levels before his oxygen ran out. The parachute research was directed at fighter pilots who were by this time flying very fast at extreme altitudes. 3. The air is incredibly thin at the altitude he jumped from. He experienced no indications that he was even falling – there wasn’t enough air to slow him down or to create a wind whisling by. He just kept accelerating – his terminal velocity was very near, maybe over, the speed of sound, but there was no buffeting or “sonic boom”. No physical sensation whatever. When he fell far enough for the atmosphere to be significant he was, of course, subject to normal aerodynamic forces and slowed down to more reasonable speeds. 4. The speed of sound is dependent only on temperature and composition of the medium, not altitude or pressure, although temperature correlates with altitude. Very cold air has a much lower speed of sound, so his actual velocity was much less than the speed of sound at normal temperatures. 5. This is one of those deals where truth is probably stranger than fiction. He was one extreme dude – it’s possible he didn’t go quite fast enough to break the speed of sound but he sure came a lot closer than anyone else ever has. * * * If man was meant to fly faster than the speed of sound he would have been born with 50,000 pounds of thrust. ---
**Author:** ![pluto](https://avatars.discourse-cdn.com/v4/letter/p/f08c70/32.png) [@pluto](https://boards.straightdope.com/u/pluto)\ **Post date:** [November 5, 1999, 12:48am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/33 "1999-11-05T00:48:00Z")
## Geez, I just noticed the irony of my sig line! If man was meant to fly faster than the speed of sound he would have been born with 50,000 pounds of thrust. ---
**Author:** ![mr\_john](https://avatars.discourse-cdn.com/v4/letter/m/8baadc/32.png) [@mr\_john](https://boards.straightdope.com/u/mr_john)\ **Post date:** [November 5, 1999, 1:08am UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/34 "1999-11-05T01:08:00Z")
WHAT? Did somebody say somethin? Speakup! I caint hear you! HUH? What? Dayum tha grounds comin up awful fast. WHAT? ---
**Author:** ![funneefarmer](https://avatars.discourse-cdn.com/v4/letter/f/9fc348/32.png) [@funneefarmer](https://boards.straightdope.com/u/funneefarmer)\ **Post date:** [November 5, 1999, 12:47pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/35 "1999-11-05T12:47:00Z")
[http://www.afa.org/magazine/valor/0685valor.html](http://www.afa.org/magazine/valor/0685valor.html) This Air Force Magazine article gives some info along with claiming that he did go supersonic. ---
**Author:** ![pluto](https://avatars.discourse-cdn.com/v4/letter/p/f08c70/32.png) [@pluto](https://boards.straightdope.com/u/pluto)\ **Post date:** [November 5, 1999, 2:46pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/36 "1999-11-05T14:46:00Z")
Two books on the subject – _The Long, Lonely Leap_ by Joseph W. Kittinger with Martin Caidin. _The Pre-Astronauts: Manned Ballooning on the Threshold of Space_ by Craig Ryan. Caption for the dust jacket photo on the back cover of _The Pre-Astronauts_: > [@](#): > > Capt. Joseph Kittinger jumps from an open gondola 103,000 feet above Earth for a freefall at the speed of sound. This extraordinary feat by one of America’s most daring space pioneers on August 16, 1960, has never come close to being equaled. When astronaut Alan Shepard was asked if _he_ would have jumped, he replied without hesitation, “Hell no. Absolutely not.” According to Ryan, “as he fell through the 90,000 foot mark he was traveling at an almost unbelievable airspeed of 614 MPH, on the verge of the speed of sound.” In an accompanying footnote he adds, “The speed of sound … in the tropopause … is only about 660 MPH.” The balloon, Excelsior III, was launched at 5:29 a.m. Kittinger jumped at 7:10 a.m. The freefall lasted four minutes and thirty-seven seconds. His main chute opened at 18,000 feet. ## If Ryan’s figures are correct his peak Mach number was only 0.93. If man was meant to fly faster than the speed of sound he would have been born with 50,000 pounds of thrust. ---
**Author:** ![Whammo](https://avatars.discourse-cdn.com/v4/letter/w/8dc957/32.png) [@Whammo](https://boards.straightdope.com/u/Whammo)\ **Post date:** [November 5, 1999, 3:52pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/37 "1999-11-05T15:52:00Z")
Hmmm… seems like I posted a thread about this once… not too long ago [http://www.straightdope.com/ubb/Forum3/HTML/002399.html](http://www.straightdope.com/ubb/Forum3/HTML/002399.html) Like yogi berra says… its deja vu all over again… ---
**Author:** ![shiningnight](https://avatars.discourse-cdn.com/v4/letter/s/71e660/32.png) [@shiningnight](https://boards.straightdope.com/u/shiningnight)\ **Post date:** [November 5, 1999, 5:49pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/38 "1999-11-05T17:49:00Z")
Did this guy lose some buddys over Roswell a decade or so earlier ? Project “mogul” doesn’t sound quite so, so, umm you know, corny or made up now. I thought they just resently made the first none stop around the world baloon flght. ---
**Author:** ![GasDr](https://avatars.discourse-cdn.com/v4/letter/g/ba9def/32.png) [@GasDr](https://boards.straightdope.com/u/GasDr)\ **Post date:** [November 5, 1999, 9:49pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/39 "1999-11-05T21:49:00Z")
THANK YOU PLUTO!!! Shit, these guys can’t just take somebody’s word. My reference is the damn Discovery Channel…that’s it, exactly how Pluto described it. ---
**Author:** ![pluto](https://avatars.discourse-cdn.com/v4/letter/p/f08c70/32.png) [@pluto](https://boards.straightdope.com/u/pluto)\ **Post date:** [November 5, 1999, 9:58pm UTC](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529/40 "1999-11-05T21:58:00Z")
GasDr – Yeah, this can be a tough crowd. But there are so many unsupported stories out there that we’re all skeptical. One of my rules of thumb is that extraordinary claims require extraordinary proof. And this certainly is an extraordinary claim! shiningnight – Some of the mysteries at Roswell were due to covert Air Force operations, but I don’t think it was Kittinger’s group. IIRC, the culprit was Corona. These were spy satellites that returned their film cartridges to earth (i.e. Roswell) after exposure. The whole thing was super secret – even the existence of the project was classified. So when strange things were seen in the sky the Air Force had to use the “weather balloon” story as a cover. ## AFAIK, there never were any little green men involved, but they didn’t show me the pictures they took! LOL! If man was meant to fly faster than the speed of sound he would have been born with 50,000 pounds of thrust. [Previous page](https://boards.straightdope.com/t/breaking-the-sound-barrier-without-an-engine/4529.md?page=1)