Airplanes, why?

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Were all the surface skins on the jets I rode on holiday (Boeing 737/Airbus 310) flush riveted and not welded ?
Reply:Because rivets Give..Bend..Sway..And roll with the punches....Welds..Crack..Snap..Break..And cause much damage when they can and will let go..There's a reason for everything..Lesson over.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:If i remember correctly, airplane skin isnt weldable. I have an airforce buddy who does structural repair on fighter planes.Miller Syncrowave 200Hobart Handler 140Thermal Dynamics Cutmaster 38E-Z Tube BenderPlasma Cam DHC2
Reply:Rivets allow more flex than a weld does.  Welds tend to crack when flexed (which you dont want happening at 30,000 feet).  And yes, most of the time they use 7075 or something like it for skins.  AF uses all sorts of wierd alloys.Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:Inspection and repair is another reason. Airplanes are torn apart periodically for inspection and repairs. Rivets are easily drilled out and re riveted without damaging the panel.Patriot Performance AutoLincoln Power Mig 255CLincoln AC-225 StickVictor Journeyman O/AQuincy QT-5 Compressor
Reply:Thanks for the answers.So welding isn't the answer for everything  ?
Reply:Yea, I know, youd think theyd let us weld a little bit.  I saw a post where they tig welded the sheets on a patriot missle directional fin.  They used plug welds.  very slick.Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:Aircraft alloys are not weldable.  There are some components that are being joined by friction stir welding.  Imagine clamping the edge of two sheets against each other then forcing a spinning rod through the joint melting and stirring as it goes.  The heat affected zone is very limited or non existent.  If you did conventionally weld alloys such as the 7000 series you would have to heat treat afterward.   Conventional riveted construction is over fifty years old.  The commercial airline industry is slow to change.  I expect that a proven safety history has something to do with it.    Carbon fibre, adhesives and composite construction is coming but it is a slow process.  The military, of course, leads the way.
Reply:The above responses are basically correct. There are a few places that you can find very thin sheet metal assembleys in lesser critical areas spot welded. Such areas would be attaching inner skins to helicopter doors, chart holders, inner skins of avionics bay doors and other parts like that. Yep, cracking around the spot welds becomes a problem. In riveted parts tend wear the rivet holes out befor cracking. This is a simple repair job. Normally you just drill the rivet out, drill the hole to the next size and install a new rivet. In some cases even oversized rivets, which are like going a 1/2 size over are available. There are limits to how many times you can step up rivet sizes.
Reply:There are several things that are welded on large aircraft, all the high temp/titanium or stainless steel ducts are tig welded, engine ducts, apu ducts and air delivery for aircycle machines for for hot or cold air in the cabin, door thresholds are welded to repair them (not on aircraft) several misc brackets are welded up.Basic frame/fuselage is all riveted, hylocks, hucks and bolted. All inspection panels have screws not rivets, if you have to drill a rivet then you are doing a repair of some sort.Boeing is working on an all composite aircraft, I can see it as being a pain to repair outside a major repair station.
Reply:Archer, You got me on that on but I was limiting my answer to aluminum. Steel tube engine baskets are welded and shouldn't forget rag covered steel tube fuselages. I seen some turbine engine vane rings that were repaired by electron beam welding. We used to have to scrap them. It was the best welding I've ever seen.