why are oval windows used in aircrafts?

Answer 1

Physical stress.

The first commercial jet airliner (the British-made Comet) had some accidents that were traced to the larger square/rectangular windows that were used...this forced a redesign - which other manufacturers copied for safety reasons.

Answer 2

The windows are oval to reduce the stresses in the window due to differential pressure. A square window would have very high stresses in the corners and along the diagonals. The oval provides a more uniform distribution of the force. The window is oval not round because the fuselage of the plane is curved (roughly cylindrical). If you have every drilled a hole in a pipe you would note that it ends up an oval not a circle due to the curvature.

So bottom like they are oval to maximize the safety of the aircraft. I also think round would look funny, like a flying boat.

Answer 3

Certainly one of the most tragic stories of the jet age revolves around the unfortunate de Havilland Comet. Building on the British lead in jet engine technology following World War II, de Havilland developed and flew the first commercial jet aircraft in 1949, several years ahead of rival Boeing in America. Known as the D.H.106 Comet, the ailiner used four of the new de Havilland Ghost 50 turbojet engines mounted in the wing root leading edge of an otherwise fairly typical commercial airliner of the day.
Because it represented such a revolutionary advance in commercial travel, the Comet was put through an extensive series of test flights and certifications over the next three years. These 500 hours worth of flight crew training and proving flights included long overseas flights, tropical operations, and high altitude takeoffs.

Having successfully completed these tests with no apparent difficulties, launch customer BOAC received permission to begin commercial operations in early 1952. The first hint of trouble with the design came exactly one year after these operations began when a Comet mysteriously crashed shortly after takeoff on 2 May 1953. Two similar crashes in early 1954 forced British authorities to ground the entire fleet pending investigation. Over the following months, extensive tests were performed on the aircraft to determine what could have caused these mysterious accidents.

The answer finally came after a fuselage had been submerged in a tank of water and repeatedly pressurized and depressurized to represent repeated flight cycles. After several thousand of these cycles, fatigue cracks were found to be spreading from the square edges of the windows in the passenger cabin. These cracks would eventually reach a critical size where they would grow rapidly resulting in a catastrophic depressurization that would destroy an aircraft in flight.

All Comets then in service or under construction were either scrapped or modified with rounded-corner windows to correct the fatugue problem. Nevertheless, it took four years for the aircraft to be recertified for commercial service. By this time, the much improved Comet 4 series was available, equipped with better engines, greater fuel capacity for increased range, and a lengthened cabin for additional passengers.

However, the four year hiatus in Comet operations had driven most prospective customers to the rival Boeing 707 and Douglas DC-8 which soon claimed the bulk of the market. Only about 90 Comets ever reached commercial operators, and most were removed from service by the early 1980s. A few additional aircraft were used by the military, but only the Nimrod, a Comet derivative, remains in use. Had the Comet not been plagued by a fatal design flaw, Britain might well still dominate commercial aviation today.

Answer 4

As became already stated, to ward off cracks. Cracks can unquestionably enhance under rigidity, surprisingly oscillating stresses that are worry-loose to the ordinary pressurization and depressurization of airplane cabins. Cracks are an rather super deal on airplanes. there's a severe crack length in a pressurized equipment which will reason the equipment to blow up i.e. the crack to propagates on the value of sound interior the medium and equipment stress blows it up. think of appropriate to the popping of a balloon. in case you place a pinhole whilst the balloon isn't under quite some stress, it won't blow up yet you get to a ingredient very immediately will it is going to violently explode. We found out approximately this the stressful way in aviation. The british Comets have been exploding after X style of flights because of the fact the spacing of the spars have been extra beneficial than the severe crack length.

Answer 5

So it doesn´t have any edges or sharp cornes... Corners are "stress concentrators"... So when exposed to a stree, an oval window will disipate it thourgh the whole area, but a rectangular one will concentrate it in the corner, producing failure at lower stresses

Answer 6

In the wise words of Mr. Miyagi, "wax on, wax off." Windows are easier to clean if they're elliptic.

Answer 7

It's the choice of the designer. I've seen "square" and "rectangular" ones also with rounded corners.

Answer 8

design some thing new like round or anyother and send to airline compnies

you never know may be next time you fly your flight's window is round...

Answer 9

round shapes tend to be stronger than rectangular ones..

Answer 10

because
Same concept as an egg... strength... every part has a radious which means less cracks from vibration...