Opening a door in flight

[Helo]

Just a quick question from a curious passenger, in light of recent air rage incidents ....

Is it actually possible to open a door in flight when the aircraft is pressurised?

Apologies if this has been asked before, but I've done a search and couldn't find anything.

Thanks

[expedite_climb]

No it is not possible, unless your arms are strong enough to apply 9 or 10 tonnes of force. (although you may move the handle.

The reason is they are 'plugs', i.e. the door is bigger than the hole they fit in, and the pressure inside is considerably greater than that outside.

[DesignerChappie]

Not all doors are true plug doors, like Boeings. Some are Semi-plug doors and held in by abuttments in the door surround. However the answers the same, you might get the 'shoot bolts' to disengage but the door wil not open.

[Helo]

Thought so!! Thanks for the info :)

[Propellerhead]

up to 8.65 psi holding the 6' by 3' door shut, so unlikely!
eg) 22000 lbs or 10000kgs (10 tonnes) - the same static thrust as the B737 engine!!

I've occasionally forgotton to depressurise the cabin after landing (we land slightly pressurised at about 0.1 psi). The cabin crew struggle to open the door with 0.1 psi (around 120 kg), and I know even the dv window requires a good pull.

[Departures Beckham]

What about the powered doors that rather than opening outwards, open upwards (I think some 75,76 and 777's have them). Is the 'power' only available when gears are down, in which case, what about opening it manually as you would in an emergency?

[GlueBall]

The answer is the same. Neither the door motor nor the spring have enough force to overcome the force of pressurization. :rolleyes:

[trustno1]

This is comforting to know. When seated at an exit on a 747 for example I am always a little nervous to see someone loitering around the exit. I have a little fear that one day someone is going to try to open it.:eek: :eek:

[OzPax1]

As an ex ground crew, i used to find it fascinating watching how aircraft doors open/close. Their are quite a few different variations!

On Boeing aircraft for example (excluding 767 which use doors that lift into the sidewall/ ceiling cavity), the doors initaly lift out of the 'locks' (these look like liitle bolt holes all around the door frame) and move inwards slightly, the door then translates slightly towards the hinge and can then be pushed out through the gap it has just vacated. The door keeps rotating around the hinge until the door comes to rest, almost against the outside of the aircraft fusalage.

I stand to be corrected by someone more knowledgable in their operation . I have just put here what I have observed.

[av8boy]

Puts me in mind of my days, long ago, as a crew member on a USAF C-141...

We were in cruise half way between Hawaii and Japan and everyone had congregated on the large flight deck. I sat in the outboard ACM seat and chatted with a 20-year 141 veteran flight engineer. The conversation turned to the pressure differential between where we sat and the atmosphere just outside the aircraft. I began to ask questions related to the number 1 escape hatch on the ceiling of the flight deck...

Me: "Is there any danger of that hatch opening up during flight?"
Him: "Nope. It's a plug, put in from the inside. The hatch is pushed against the seal by the pressure inside the aircraft."

Me: "So, even if I opened the latch it wouldn't open up?"
Him: "Not a chance.”

Me: "How about if I opened the latch and pulled really hard on the handles?"
Him: "Even if we all pulled together, the handles would come off long before the hatch opened up."

Me: "Really? It's in there that good?"
Him: "Yup. I guarantee it."

Me: "Well then, I'm going to give it a try!"
Him: "What the hell is wrong with you boy? Do you want to get us all killed? Do you understand what would happen if that damned thing opened up right now?"

I've always reflected on this conversation with a chuckle, even now, some 25 years later. To me, it has always demonstrated the tension between what we KNOW when it comes to aviation, and the real human gut-check that always seems to be required. In the same way, I recall how I flew for perhaps 6000 hours in 141s before I stumbled across the fact that if you pulled up one of the pallet rails during cruise on a sunny day, you could look through the aircraft floor at the skin on the belly of the airplane and see just how thin and perforated it was, with sunlight streaming in all over the place. All of a sudden I was an acrophobe. It was the first time that I actually felt as though I was really high up in the air... the same feeling as being on top of a tall building. Oddly, I had never gotten that sensation from flight before that day... It had always seemed different to be in an aircraft than it did being on top of the roof of my house, until then.

I just love this conversation!

Dave

PS I got better, thank you.