Power Gel question

[sapblatt]

Curious - have any of you ever packed PowerGels (or anything like them) for an airplane flight? I am not sure if the air pressure will cause issues and make them explode. I have seen Pringles cans nearly burst only as high as T-storm junction...really do not want a huge mess when I arrive...

 

[nancy]

I have used gels at elevations above 19,000 ft. They are about the only thing I can 'eat' at higher altitudes. Never had a problem on the airline or in my pack.

 

[SAR-EMT40]

If they are in your carry on you probably have nothing to worry about because the cabins are usually at a pressure of no higher then around 8000 feet IIRC. A quick check will probably find that info. Checked bags might be a different issue. If you are really worried do what I do with anything I am afraid will leak. Put them in zip locks. Greatest invention since sliced bread and cheap insurance.

Keith

 

[UNFROZENCAVEMAN]

...Greatest invention since sliced bread and cheap insurance.
Keith

Wait, when was cheap insurance invented?

Kidding aside, won't gel packs (gel being the key word here) raise some eyebrows if you're trying to carry them onto a plane? I haven't flown in a couple of years so I'm only assuming here....

 

[DougPaul]

If they are in your carry on you probably have nothing to worry about because the cabins are usually at a pressure of no higher then around 8000 feet IIRC. A quick check will probably find that info. Checked bags might be a different issue.

The cargo hold is also pressurized--otherwise the cabin floor would bow downward.

Doug

 

[DougPaul]

Kidding aside, won't gel packs (gel being the key word here) raise some eyebrows if you're trying to carry them onto a plane?

I had the same thought. If there are concerns, I suspect they are more likely to be acceptable in checked luggage than in the cabin.

Doug

 

[Kevin Rooney]

Here's another solution - place the items in your checked luggage, and inside a Nalgene bottle and tighten the lid like you would for any liquid. Doesn't really matter which model Nalgene, they're all plenty strong. The internal pressure of the Nalgene will remain the same as where it was packed, so pressure fluctuations in flight won't have any impact on your gel packs.

There's nothing magical about a Nalgene, as any sturdy, airtight container will provide the same protection. I mention Nalgene because chances are you may already be packing them -

Kevin

 

[bikehikeskifish]

Excellent idea, Kevin.

I use the Nalgene or Gatorade or any other bottle to demonstrate the laws of pressure to my kids. "How come this thin plastic Gatorade bottle is crushed when I return to the house?" Why does the air rush into my Nalgene bottle when I get home and open it. It's even more fun when they can do the experiment themselves -- I had my daughter put a plastic 500mL water bottle in her pack when we climbed Cardigan and drink it all before coming down...

Tim

 

[Nessmuk]

If they are in your carry on you probably have nothing to worry about because the cabins are usually at a pressure of no higher then around 8000 feet IIRC.

Yes, cabins and cargo holds. As I recall from my crew days, 8000 ft cabin altitude in the daytime, 5000 at night (when you may not be at peak performance and need the extra O2). But why would there be a problem anyway? Unless the packages contain substantial air pockets sealed within the packet, there would be no expansion. Liquid gel does not expand under reduced pressure and thus no internal package pressure at altitude would be present.

 

[Kevin Rooney]

Thanks, Tim. Because of where I live now, it's interesting to see what expands as you reach the summit. You should see what happens to the wrapper on a Snickers bar when it goes from 2K' to 14K'!

Here's a shot of what happens to a empty Nalgene that is closed on the summit of a 14'er. This was taken in a motel in beautiful downtown Weed, CA after climbing Shasta several years ago:

 

[SAR-EMT40]

But why would there be a problem anyway? Unless the packages contain substantial air pockets sealed within the packet, there would be no expansion. Liquid gel does not expand under reduced pressure and thus no internal package pressure at altitude would be present.

This is a very good point. I thought that there was at least some gas in the package but, if there is no gas (air or otherwise) in the package then there will be no expansion. Liquid and of course solids are for all practical purposes incompressable and would also not expand in this context.

Keith

 

[DougPaul]

Here's a shot of what happens to a empty Nalgene that is closed on the summit of a 14'er.

I don't have any pictures, but a less dramatic version of the same happens when one brings a sealed HDPE Nalgene down from a 4-5K ft summit to sea level. I suspect that many of us have observed it.

Doug

 

[Snowflea]

To answer Mike's original question, I fly quite often and almost always have a few gels in my checked bag. Have never had a problem with one bursting, but as a precaution, I put them in a larger Ziplock. They'd probably be okay in a carry-on as far as getting them thru security, but I wouldn't count on it...