Google Loon balloon crashes near Yakima • Hacker News Board

Re: Google Loon balloon crashes near Yakima

#21

Post by toomuchtodo » Tue, Jun 03, 2014, 3:20 PM UTC

falcolas wrote: post #17

jacquesm wrote: post #10

Earlier quoted context omitted.

That's an interesting back of the envelope question to work out. Something with volume occupied by all aircraft aloft at any given moment, volume of all balloons at any given moment, the total volume of the shell in which commercial air traffic takes place. I think we can safely forget about the chances of spyplanes hitting balloons, the volume of space versus the number of spyplanes would make that a non-issue, even…

The problem is that jetliners don't have all that space you calculated to play around in. They actually have a few well defined corridors and altitudes in which they can operate - the straight lines drawn from one VOR (effectively equivalent to a major airport) to another at 1,000 foot intervals. Detours are costly due to time and coordination (air traffic control, other aircraft), and reacting to seeing a balloon an…

> They actually have a few well defined corridors and altitudes in which they can operate - the straight lines drawn from one VOR (effectively equivalent to a major airport) to another at 1,000 foot intervals.

Until NextGen (ADS, etc) finishes its rollout and everyone flies direct instead of on Victor airways and VOR to VOR.

Re: Google Loon balloon crashes near Yakima

#22

Post by jgrahamc » Tue, Jun 03, 2014, 3:44 PM UTC

robin_reala wrote: post #14

gregholmberg wrote: post #6

In the 90s, I would sometimes trip over ethernet cables that had been strung between server racks, across an aisle. Will this be the decade where I get to experience being struck by falling routers and switches, far from any data center? (EDIT: Simply remarking on novelty of problem and upward growth of network. No criticism of any firm implied or intended.)

I took down an AS/400 server once by tripping over two Type 1 token ring cables[1] that had been plugged together in the middle of a walkway. No-one ever owned up to that setup. [1] http://en.wikipedia.org/wiki/File:IBM_hermaphroditic_connect...

Given that it was token ring that might have isolated the AS/400 but the MAU would have healed the ring and everything would have been fine.

Re: Google Loon balloon crashes near Yakima

#23

Post by falcolas » Tue, Jun 03, 2014, 3:51 PM UTC

toomuchtodo wrote: post #21

falcolas wrote: post #17

Earlier quoted context omitted.

The problem is that jetliners don't have all that space you calculated to play around in. They actually have a few well defined corridors and altitudes in which they can operate - the straight lines drawn from one VOR (effectively equivalent to a major airport) to another at 1,000 foot intervals. Detours are costly due to time and coordination (air traffic control, other aircraft), and reacting to seeing a balloon an…

> They actually have a few well defined corridors and altitudes in which they can operate - the straight lines drawn from one VOR (effectively equivalent to a major airport) to another at 1,000 foot intervals. Until NextGen (ADS, etc) finishes its rollout and everyone flies direct instead of on Victor airways and VOR to VOR.

True, but even then there will still result in "air highways" from airport to airport.

Re: Google Loon balloon crashes near Yakima

#24

Post by jbigelow76 » Tue, Jun 03, 2014, 4:00 PM UTC

robin_reala wrote: post #14

gregholmberg wrote: post #6

In the 90s, I would sometimes trip over ethernet cables that had been strung between server racks, across an aisle. Will this be the decade where I get to experience being struck by falling routers and switches, far from any data center? (EDIT: Simply remarking on novelty of problem and upward growth of network. No criticism of any firm implied or intended.)

I took down an AS/400 server once by tripping over two Type 1 token ring cables[1] that had been plugged together in the middle of a walkway. No-one ever owned up to that setup. [1] http://en.wikipedia.org/wiki/File:IBM_hermaphroditic_connect...

My hands down favorite Dilbert comic ever was a token ring joke:

http://dilbert.com/dyn/str_strip/000000000/00000000/0000000/...

Re: Google Loon balloon crashes near Yakima

#25

Post by hueving » Tue, Jun 03, 2014, 4:03 PM UTC

gregholmberg wrote: post #16

kordless wrote: post #15

The word 'crashes' could easily be substituted with 'drifted into'.

Dropping at 2000 feet per minute is not quite free fall, but it's a long way from a drifting dandelion seed. I wonder if the balloon payload left a crater.

At 22 MPH? Probably not considering it has to be light enough to be a balloon payload in the first place.

Re: Google Loon balloon crashes near Yakima

#26

Post by robin_reala » Tue, Jun 03, 2014, 4:10 PM UTC

jgrahamc wrote: post #22

robin_reala wrote: post #14

Earlier quoted context omitted.

I took down an AS/400 server once by tripping over two Type 1 token ring cables[1] that had been plugged together in the middle of a walkway. No-one ever owned up to that setup. [1] http://en.wikipedia.org/wiki/File:IBM_hermaphroditic_connect...

Given that it was token ring that might have isolated the AS/400 but the MAU would have healed the ring and everything would have been fine.

Oh god, I’d blocked from my mind the pain of ring dropping. We had MAUs for the servers, but for some reason ran the rest of the office on CAT-5 TR gear from Madge without any MAUs. Just took someone to unplug and that section of the office would lose network connectivity.

Re: Google Loon balloon crashes near Yakima

#27

Post by toomuchtodo » Tue, Jun 03, 2014, 4:20 PM UTC

falcolas wrote: post #23

toomuchtodo wrote: post #21

Earlier quoted context omitted.

> They actually have a few well defined corridors and altitudes in which they can operate - the straight lines drawn from one VOR (effectively equivalent to a major airport) to another at 1,000 foot intervals. Until NextGen (ADS, etc) finishes its rollout and everyone flies direct instead of on Victor airways and VOR to VOR.

True, but even then there will still result in "air highways" from airport to airport.

I would agree with this. Still, the number of "air highways" would increase drastically.

Re: Google Loon balloon crashes near Yakima

#28

Post by jgrahamc » Tue, Jun 03, 2014, 4:41 PM UTC

robin_reala wrote: post #26

jgrahamc wrote: post #22

Earlier quoted context omitted.

Given that it was token ring that might have isolated the AS/400 but the MAU would have healed the ring and everything would have been fine.

Oh god, I’d blocked from my mind the pain of ring dropping. We had MAUs for the servers, but for some reason ran the rest of the office on CAT-5 TR gear from Madge without any MAUs. Just took someone to unplug and that section of the office would lose network connectivity.

:-)

I used to work for Madge. Why were you running without MAUs?

Re: Google Loon balloon crashes near Yakima

#29

Post by plantain » Tue, Jun 03, 2014, 4:42 PM UTC

plantain wrote: post #19

jacquesm wrote: post #11

Earlier quoted context omitted.

At the speed your average jet is travelling and the fact that approximately half the traffic is at night I'd hope for a radar transponder on the balloon (or at least some kind of reflector) because I highly doubt you'd be able to respond in time when going on visual cues alone, you'd need at least a few kilometers warning.

They have ADS-B transponders. You see them sometimes on flightradar24 floating around at FL650.

http://theaviationist.com/2014/03/01/google-project-loon/

Re: Google Loon balloon crashes near Yakima

#30

Post by mscuwa » Tue, Jun 03, 2014, 4:53 PM UTC

jacquesm wrote: post #3

tim333 wrote: post #2

Guess that's a hazzard of balloons all over the place. Hope one does not take out a jet.

The chances of hitting a jet are remote, the balloon would have to loiter at the right altitude for that chance to increase appreciably. Most will go higher, pop and then fall. The barrage balloons of WW-II had to be anchored very carefully to avoid having them go into the stratosphere. As the balloon expands (which it does when it goes higher) it will become more buoyant, not less so there is a positive feedback loo…

Are you sure about positive feedback? Balloon does expand, but air outside becomes thinner, so buoyancy will actually stay constant until the walls are completely unfold, and then drop as gas inside will expand less than necessary to maintain buoyancy.