Why Aren’t The Boeing 737’s Main Wheels Covered In Flight?

If you look at the underside of the Boeing 737 shortly after takeoff or in flight, you will see that the main landing gear wheels sit exposed after folding into their housing. On most other aircraft, it is covered by closing doors. This has been the case since the first 737 was introduced - but why is this?

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[jaylockwood]

Other youtubers take 25 minutes to answer this.
Congrats on getting to the point!

[cskvision]

How ironic the main selling feature of having the aircraft lower to the ground 60 years ago is now its biggest design hinderance to enhance engine and fuel efficiency to compete with the A320neo.

[kevinjalfonsov]

Finally, one of the biggest questions in aviation answered!

[neilpickup]

Interestingly, the latest version of the Embraer has full doors. So perhaps the advantage/disadvantage balance is shifting.
Although the ground clearance issue did confuse me as the doors usually only open while the undercarriage is being raised or lowered.

[dynasty]

Because it's simpler and cheaper, also due to the 737's low ground clearance.

[trijetz]

Short answer: to keep it cheap, and its landing gear is very short.

[Inkling]

Some aircraft, specifically the C-47 and the A-10, don't fold their landing gear away. They merely retract it upward. In situations where the gear won't deploy, it is still there, extending a short distance below the fuselage and allowing the plane to make a belly landing with less damage.

[justinhallluper]

The fact I've never actually ever noticed this! Good to know.

[halcyongeezer]

2:08 ‘Boeing preferred wing mounting to increase fuselage width’: why would tail mounting restrict fuselage width, when there are other tail-mounted aircraft with of similar size, like the VC10, Il-62 etc? Couldn't find any fuselage width stats for those two, but they're all 6 seats abreast, then there are twin-aisle tail-mounted jetliners like the Tristar, DC-10 etc. Thanks.

[seanluo]

Issue with the 737 being so low: The large 737 MAX engines resulted in placements which caused imbalance and the need for MCAS.

[Major_Tom]

To answer the question at the end of the video: the CRJ’s have the same landing gear configuration.

[AlexDahlseid]

The Boeing 737 isn’t the only aircraft to have exposed landing gear such as the CRJ series of aircraft, DC3/C47 SBD, F4F, PBY, B24 and German aircraft modified for use on the eastern front. The exposed gear design does appear in fiction with Betty’s Hyper Galactic Starcruiser in Atomic Betty series having the exposed red landing pads.

[ryanhan]

i have been asking this for monthes before you made this vid- Great job

[windanthonystream]

The DC-9 and 717 sits lower than the 737 and it has landing gear doors.

[Orca]

In addition to some civilian aircraft like the 737 and the others mentioned near the end of the video, having the landing gear wheels exposed when retracted is also a feature of some WW2-era military aircraft, such as the F4F Wildcat, SBD Dauntless, and variants of the PBY Catalina which were equipped with retractable landing gear. Also, the modern A-10 Thunderbolt II has the wheels of the main landing gear partially exposed when retracted as well.

[Calebs_Aviation]

At 3:03 A lot of small general aviation aircraft(If they even have retractable landing gear) like most Piper aircraft or Mooney aircraft just have retractable gear and no doors to cover the landing bays.

[franzfanz]

I like them. It reminds me of old WWII designs with their partially covered designs.

[spongebubatz]

The CRJ-Family also has the same type of design with their main landing gear

[joydasgupta]

Didn't mention anything about the effects on tyres due to open?

[captainclone]

Wrong!! The lack of landing gear doors is NOT about ground clearance!! I worked for Boeing for 33 years, retired 2010, as a structural design engineer so ground clearance is not the reason. To put it simply it's was a weight saving initiative. There also use to be a inflatable rubber tube that inflated around the stowed MLG tire sealing the wheelwell. That was later discarded for weight and cost savings reasons. Now ground clearance is the cause of the 737 Max problem. A larger diameter engine nacelle was required but the landing gear could not be lengthened, easily. So the Max team canted the engines up to provide the clearance which caused an aerodynamic problem requiring a computer input into the flight control system. Bad idea.