Differences Between Planes

[Guest fyrestrtr]

I was doing my regular weekend trawl over the flight sites -- and a question came up; thought I'd ask the experts in here.There are a lot of planes that to me look similar. Is there a reason (other than say "family" presence -- ie, airline prefers all Airbus) to chose one or the other?For example:A320 vs. B737To me, other than the design differences, these two look almost the same. I don't know performance/range wise, so I'm hoping others can chime in. Are these planes used on the same routes by different operators? Is there a concrete difference between the two?Another one that I am curious about:Saab 340B vs. EMB 120Would love to hear your opinions and other aircraft that are similar in target. One more I just thought of ..A330 vs. B767Thanks for your opinions -- and happy holidays.

[Guest airbus2]

HeyThere are many choices for operators choose between different aircraft, the example in the question (737/A320) is a good one.The A320 has a range of 5700km fully loaded it can carry 180 people in a single class configeration. Its direct rival in the 737 range would be the 737-800. This has a range of 5665km and a seating capacity of 189. So the A320 will take you further, but the 738 will take more people but not as far, it is swings and roundabouts. The A320 is more environmentaly friendly and has lower maintenance costs making it more attractive to buyers - especially with governments (well the UK anyway!) thinking about green taxes etc. Also when a company buys a jet, it makes more sense to keep to the same family, for example the A318, A319, A320, A321 all have the same cockpit layouts so pilots can fly all of them with little or no retraining allowing for better crew flexibility. British Airways flies the 737 to Izmir in Turkey, yet Mytravel flies to Bodrum (just to the south of Izmir) using A320s.There are lots of factors to consider for airlines, the most important being range, capacity and fuel economy. Apart from this the family is important, i cant see Mytravel buying any 737s as it would require complete retraining of all their A320 crew etc. Hope this answers your question.Dave

[Guest Mr Chips]

In many ways the shape is dictated with current technology and materials because amongst other things aeroplanes need to be stiff and light and aluminium needs to be structured in a certain way to achieve this. I suspect composites could start to change things as, due to the stiffness and lightness more options are becoming apparent. Regardless, look at the basic requirements:1) High Mach speeds of .78 to .84.2) Low drag3) Multi-engined4) High altitudes5) Stable and easy to fly6) Carry large loads over a wide CofG7) Easy to land.1) means swept wings and shock wave compatible profile. 2) Means swept wings and a pointy nose, retractable gear, etc. As 1) and 4) means jet engines then 3) means engines arranged laterally across the aircraft. 5) and number 6) means large fins and horizontal stabilisers. 7) means lots of flap area with the possible addition of speed brakes to create a high drag configuration increasing speed stability when at low approach speeds.There are some options for achieving 5): * You can go high wing or low wing with dihedral. Short, take-off and landing (STOL) aircraft are usually high-wing because it is easier to land firmly due to lower ground effect and STOL is often associated with rough surfaces so it pays to have the engines up high an away from ground as much as possible. High wing usually means having a T-Tail.* If you have low-wing you can put the engines under the wings on at the rear of the fuselage (like an MD80). Engines in pods under the wings maximise the amount of space available for carrying payload and also permit a standard tail as T-tails have been associated to nasty handling qualities. Also, maintenance access is easier. But engines in pods change the airplane's attitude with power because the thrust line is different from the drag line, increase asymetric loads if an engine fails (as they are further apart), are more prone to Foriegn Object Damager (FOD) and compressor stall with reverse thrust and strong crosswinds or low speeds and they are noisier in the cabin.I'm sure there are other lots of other factors, but I hope that provides an idea of why some are so similar to others.

[Mace 1,902]

>For example:>>A320 vs. B737>>To me, other than the design differences, these two look>almost the same. I don't know performance/range wise, so I'm>hoping others can chime in. Are these planes used on the same>routes by different operators? Is there a concrete difference>between the two?>To me, a 737 and A320 don't really look the same. The 737 looks fatter and has a huge tailfin. Whereas the A320's appear to be narrower, with a smaller tail, and less swept wings.A318/A319/A320/A321 all use the same cockpit as was said. That's nice for a lot of airlines in training and cross-over purposes.The A320's use a sidestick controller, which is essentially a joystick controller rather than a yoke. That's quite a change from the 737's more traditional yoke layout. Also A320's are fly-by-wire and have more of a computer-controlled flight regime. A Boeing 737 is more of a traditional "fly it" aircraft.For airlines it's a matter of economics and what they are used to flying.RhettAMD 3700+ (@2530 mhz), eVGA 7800GT 256 (Guru3D 93.71), ASUS A8N-E, PC Power 510 SLI, 2 GB Corsair XMS 3-3-3-8, WD 250 gig 7200 rpm SATA2, CoolerMaster Praetorian

[Guest airbus2]

"The 737 looks fatter and has a huge tailfin. Whereas the A320's appear to be narrower"Ive heard a few people say this and also relates to another important factor. The A320 has the widest cabin cross section it its catagory, allowing for airline to have wider more comfortable seats yet maintaining a decent sized walkway which results in better comfort, ease of movement and quick turn-around times. Airlines like planes that increase flexibility so that they can taylor it to their needs. Also the A320 cabin has bigger overhead bins than any aircraft in this catagory.Big visual difference between the A320 and 737 would be that the A320 has a rounder nose, unlike the 737s pointy one. the A320 has doors on its main landing gear and round engines, unlike the "hamster cheak" engine design of the 737. Dave

[michal 44]

>There are a lot of planes that to me look similar. Is there a>reason (other than say "family" presence -- ie, airline>prefers all Airbus) to chose one or the other?The same way some people buy Mercedes while other prefer BMW. Some prefer vanilla ice cream while other favor chocolate. Not much different with aircraft choice. Michael J.

[Guest CRJ700FO]

The widebody airbus market is kinda dead compared to boeings recently. My guess is widebody airbus a/c can be bought on the cheap now.I'll take a stab at the saab 340 versus emb 120.They do look differently. The Emb 120 has a shorter nose gear and leans down versus the saab. I have heard good things about both a/c. With todays environment I doubt anyone would be purchasing either of them as both are limited to about 90% capacity with the new FAA pax weights.The Emb 120 is slightly faster and has that silly big wheel yoke.As far as outside differences between the 737 and A320 its fairly obvious looking at them. One looks like a guppy (737) and the other looks short and stubby and rounder (A320). I can hear the A320 engines come through radio transmissions as they have a unique sound versus the boeing engines.As far as other minute differences an A318 is short and squabby. A 319 is slightly longer and has one overwing exit. A 320 is still slightly longer and has two overwing exits. A 321 is quite a bit longer.

[RFields5421 1]

The physics which impact aircraft design are going to dictate that aircraft designed for similar missions have a similar appearance for the most efficient and cost effective design.Unlike the great experimentation of jet design in the 50's - and all the ground breaking work done by military designers at that time - today's computer power can fine tune a design to a level unimaginable even 20 years ago.There are also important sets of legal considerations for some type of aircraft mission.Among these are the 19 seat and 50 seat limits.Many smaller airports do not have the AARF services for aircraft with more than 19 seats. It's an expensive line to cross. The EMB 110 was designed with this in mind.The 50 seat limit, and now 70 seat limit often have more to do with pilot union contracts and pilot certification requirements. Airlines worldwide often have contracts which allow much lower pay for a pilot of a 'regional' aircraft.

[Mace 1,902]

>"The 737 looks fatter and has a huge tailfin. Whereas the>A320's appear to be narrower">>Ive heard a few people say this and also relates to another>important factor. The A320 has the widest cabin cross section>it its catagory, I have always wondered why an A320 fuselage *appears* to be narrower than a 737's. Is this an optical illusion?RhettAMD 3700+ (@2530 mhz), eVGA 7800GT 256 (Guru3D 93.71), ASUS A8N-E, PC Power 510 SLI, 2 GB Corsair XMS 3-3-3-8, WD 250 gig 7200 rpm SATA2, CoolerMaster Praetorian

[Guest fyrestrtr]

Another thing that I noticed is that the A320 seem to have fins on both the top and the bottom of the wing, that's the easy give away for me.Having flown in both, I can say that the A320 is more comfortable and seems more 'roomier' than the 737 (both the planes I few were single class configured).Thanks for your thoughts :)