Hacker News Reader

Comment by bogomipz | Hacker News Reader

>"With less than 10k feet to go, they noticed the fuel tanks in the back were buckled inward."

I'm confused what altitude were they at then that they had only 10K feet left? From the article:

>"Because most small light aircraft are unpressurised, it's not advisable to fly above 10,000ft."

I once was in a Cessna 206 on a flight plan that took us up to 17,000 ft. You can fly that altitude fine, as long as you have supplemental oxygen (via a cannula in our case).

We took off at about 3AM, and I fell asleep immediately. Woke up somewhere well above 10K, dizzy as hell and realized what I'd done. I put in the cannula and the dizziness left within a few minutes iirc.

Your parent mentioned these were planes for a commuter airline. So they were probably pressurized.

That's what I thought maybe as well but with a commuter airline plane could you fix a problem with the fuel takes with a pocket knife? The OP stated:

>"they noticed the fuel tanks in the back were buckled inward. They weren't vented properly. A pocket knife solved the problem"

This males me think it was something much smaller that would have fuel takes within arms reach or not much further away.

Op clarified it was a Cessna 421, so indeed pressurized. When these are ferried they put fuel tanks inside the cabin (these are called ferry tanks unsurprisingly), so they were indeed within arms reach.

Yeah I didn't see his edit until after I posted that. I've actually been on one these as part of a commercial "island hopper" flight. Cheers.

10000 feet is quite a lot from a pilot's perspective. In a glider, this is at least 50 minutes assuming a 200fpm minimum sink rate in stable clear air (no thermals), and in an airplane with a far less efficient wing it might be around 10 minutes (a decent rate of 1000fpm).

10 minutes sounds awfully short if you're on your way to ditch in ice cold water, and you have no idea why all your engines have stopped. :)

Primary training is done around 1500-3000 feet above ground, so you're expected to go through your troubleshooting checklist in less than a minute. If the engine failure is on takeoff or approach to land, which is the most common phase of flight for engine failure, you have tens of seconds for troubleshooting because you must leave spare time to get configured for an emergency landing. (CFII in a previous epoch.)

A Lance or Saratoga tend to sink at 1400fpm best glide. There are many other planes that fly as well as bricks without power.

Without supplemental oxygen. If they were much higher than that, they were probably breathing some sort of oxygen system.

Reply on news.ycombinator.com