can you takeoff without packs?

[davierosoft 13]

I'm Italian, maybe you have seen the Lufthansa logo on our fuselage, the company was AirOne (italian), ex partner of LH, now part of Alitalia smart carrier.

[Daniel choen 23]

I'm Italian, maybe you have seen the Lufthansa logo on our fuselage, the company was AirOne (italian), ex partner of LH, now part of Alitalia smart carrier.

Hey Andrea, i am going to Italy next Saturday, for a ski trip(; i love your country LOL... just wanted to let you know, have a good one cheers man(;

[ICMC 1]

Ok I'm going to have a another look at the photo tomorrow. I'm assuming your mother tongue is German? The Germans, and most other mainland Europeans seem to manage English (spoken and written) to varying degrees of competency, yet how many of the British can claim to speak (or write for that matter) a foreign language? Not many, I can assure you, having grown up in the UK myself.

So I am one of a few. Speak and write another language fluentlyKewl

[JET 1 0]

There's a lot of switches that don't do much if the 'upstream' switch is off, but they still have a correct position on the checklist flow. Otherwise I'd just shutdown by turning off the engines and battery and leave it at that! :)

That's correct, prodecurally. I was talking about what happens under the hood.

[JET 1 0]

I'm Italian, maybe you have seen the Lufthansa logo on our fuselage, the company was AirOne (italian), ex partner of LH, now part of Alitalia smart carrier.

I think was looking into sending an application to AirOne, but couldn't find any recruitment info in other language than Italian. Took the hint, it's probably required .. :(

[WhiteKnuckle 11]

It might be more of a translation thing as you say, and now I've had my morning coffee I'm not annoyed anymore :). Hey Andrea, it's OK, I see you posted some interesting stuff after shooting down my packs off/bleeds off/APU post, so it's cool.Direct hit from Cyclone Heidi, if you watched the ABC news last night and saw some live footage of the cyclone well I shot that. Got the camera a little wet (it wasn't working yesterday). Actually not too much death and destruction, we've had the TV crew from Perth staying at our house and have been trying to find them something actually worth shooting!As for YPPD and aviation: the most common plane I fly on is in fact the NG, did a Virgin Blue YPPD-YPPH and a Qantas YPPH-YPPD last week. The 717 replaced the Bae146 for some of the routes a couple of years ago. For FSX, the Pilbara scenery is not great, I've been brewing a bit of home-made photoscenery for the region over the past few days and some of the inland desert is pretty amazing. A part of the world very few real or virtual pilots will ever fly over.Anyway, back on to the NG's PACS/packs...

Ah, I didn't check Virgin. Just downloaded FTX AU Red so may have a pic of your gaff (no pun intended) up on the "Red Sky" post shortly.

So I am one of a few. Speak and write another language fluentlyKewl

Ah now Gaelic doesn't count, :( but point taken.

[japascoe 98]

Actually, I beg to differ.Take an unopened 2L of Coke and go stand on it. Then drain said 2L of Coke, leave the cap on, and stand on it...Which one is more structurally sound?

The more 'structurally sound' one is the bottle containing the incompressible fluid that can resist your weight and transfer the force to the ground. However the air in an aircraft's fuselage is just as compressible (regardless of pressurisation) as the air in an empty bottle of coke. In addition the forces on an aircraft's fuselage are completely different than those on a bottle of coke that you stand on (not just the magintude, but especially the type and direction), so your analogy doesn't really work.

We must use a can of coke a bit longer with a thing called wing attached under it.Now, on take off phase the wing (where main landing gears are attached) will suffers of some vibration due to runway surface.This vibration is partially transfered to the structure. If the can is pressurized (positive pressure) the can will resist and will not flex. Without it the cabin will have a banana effect normally visible on -4/8/900 planes when on ground.I must search pictures about it.Remember that if fuselage deflect when is empty and parked, when it is doing rotation (with stabilizer and elevator forcing down and wings up) the stress will be increased.The pressure controllers will close the outflow valve automatically at the beginning of the take off phase, exactly when the throttles are advanced.The controller will add 0.1 PSID of pressure in the cabin and then, after lift off, it will start its cabin climb profile.Same thing on landing, with the difference (if altitude is set correctly) that the pressure will be .15 and not .10 PSID. This because on landing the stress is bigger.

Hmm, the forces of the wing will be transferred to the fuselage by way of the centre wing box. I am somewhat sceptical that a differential pressure on the fuselage skin will modify that in any significant way.In your first picture you show buckling of the fuselage skin due to stresses in the skin, at the area where the fuselage bending moment is the greatest. The bending moment which causes the banana effect is a result of the weight distribution within the fuselage. Since the pressure inside the fuselage is perfectly symmetrical that won´t effect the bending in any way. If the pressure inside the plane is not the same as the pressure outside the plane the stress in the skin will be higher than if the pressures were the same. I suppose a pressure differential could dampen some of the vibrations or loads on the fuselage structure, but I'm having trouble visualising how at the moment. In any case it would have to outweigh the extra stress caused by having a differential pressure.There are plenty of good reasons to make pressurisation of the fuselage prior to take-off desirable (passenger comfort, sealing the doors), I'm just not sure structural integrity is one of them.

[davierosoft 13]

The main reason is the bump effect, but also structurally the pressurization helps.The stress on the fuselage at 0.1 psid is much less than the stress in a normal flight crz differential (at around .8psid).The fuselage is alost cilindrical and the stress due to the pressurization is almost limited to the skin and its joins, forward and aft bulkhead, plus the wing box area as it results in a shape different than cylinder and pressure is not equally distributed.On the 737 the doors when closed are already part of the structure (you cannot tow or taxi with a door opened)We used coke example as a coke can will "pressurize" if shaked.If you feel better, you can use a plastic bottle with the cap removed and with the cap closed.

[davierosoft 13]

Hey Andrea,i am going to Italy next Saturday, for a ski trip(; i love your country LOL... just wanted to let you know, have a good one cheers man(;

Where? :)

[davierosoft 13]

I think was looking into sending an application to AirOne, but couldn't find any recruitment info in other language than Italian. Took the hint, it's probably required .. :(

There is no more "AirOne" except of the name of the name.Now it is part of the new "Alitalia CAI(Compagnia Aerea Italiana) " so info and recruitment should be sent to them. ;)Old website was www.flyairone.itNow, maybe you can only book from there. For other info www.alitalia.it

[Daniel choen 23]

Where? :)

Val Gardena, it's going to be amazing(;