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The Lockheed Constellation has an enormously long nose gear, which causes the aircraft to slant appreciably backwards when sitting on the ground:

L-049

enter image description here

(Image by Greg and Cindy at Flickr, modified by Cobatfor at Wikimedia Commons.)

L-649

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(Image by the San Diego Air and Space Museum, via Flickr, via Wikimedia Commons.)

L-749

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(Image by RuthAS at Wikimedia Commons.)

L-1049

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(Image by RuthAS at Wikimedia Commons.)

L-1649

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(Image by Robert Togni at Flickr, via JuergenKlueser at Wikimedia Commons. Note that, due to the gigantic nose gear, the fuselage is approximately level, despite the ground sloping downwards considerably towards the aircraft's nose.)

In contrast, other airliners of the era had a much-less-ridiculous nose gear length, like the DC-7:

enter image description here

(Image by Ted Quackenbush at airliners.net, modified by Fæ at Wikimedia Commons.)

and the Stratocruiser:

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(Image by Bill Larkins at Flickr, via Wikimedia Commons.)

Why is the Constellation's nose gear so much longer?

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    $\begingroup$ The Connie is one of the most beautiful airplanes ever IMO, saw several when they came in to the EAA one year, really graceful in the air. $\endgroup$ – GdD Apr 11 at 9:51
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    $\begingroup$ The original L-049 prototype had a much stubbier nosegear but test pilots Eddie Allen and Kelly Johnson quickly discovered that it did not reach the ground. $\endgroup$ – A. I. Breveleri Apr 11 at 18:45
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    $\begingroup$ From the picture, it seems like the main gear of the Constellation is also quite a bit taller than the others. Maybe the designers were concerned about prop clearance on rough fields? $\endgroup$ – jamesqf Apr 12 at 16:18
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The Connie's fuselage has a subtle S shaped contour which was intended to conform somewhat to the upwash ahead of the wing and downwash aft of the wing, with a final upturn at the end to place the horizontal tail at the desired vertical location.

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They also tapered the fuselage to the smallest cross sectional area possible at the nose, to part the air gently you might say, so the bottom ends up sloping up toward the nose.

Then you have main gear legs that are fairly long because the R3350's propellers are quite large.

The wing incidence is set to optimize the fuselage curvature's presentation into the airflow in cruise.

At the same time, you want to have wing chord in a certain desirable AOA range sitting on the ground, and you want to keep the tail from sitting too high (the Connie has the 3 surfaces to keep the vertical height of the tail low enough to fit the common hangars of the day).

Combine all those factors together and you end up having to the make the strut really long, and ending up with the most graceful airliner ever designed.

enter image description here

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  • $\begingroup$ I already knew about the streamlining and the tail-height restrictions, but now I see how that necessitates tilting the fuselage back slightly! $\endgroup$ – Sean Apr 11 at 2:49
  • $\begingroup$ Could you expand on having the wing at a desirable AOA on the ground? $\endgroup$ – fooot Apr 11 at 14:27
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    $\begingroup$ The wing's angle-of-attack while rolling on all three wheels. You want to be close to zero or minimal lift with the nosewheel down but not have to rotate too far to get AOA for lift off. $\endgroup$ – John K Apr 12 at 13:43
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enter image description here
(Top, bottom)

The Connie and DC-7 have the same engine (Wright R-3350), low-wing mounting, and main landing gear configuration (retraction into the inboard cowls).

If you visually remove the nose landing gear (NLG) bay door on the DC-7, it too has a tall NLG.

It's just not as tall because the big difference is the propeller diameters. Lockheed went with three bladed propellers, compared to the DC-7's four bladed propellers, resulting in a difference of 5.5 ft (1.7 m) in diameter (19 ft$^{[1]}$ vs 13.5 ft$^{[2]}$ propellers). The Connie also sat with a higher pitch angle, as evident by the 3-view drawing.

The Stratocruiser on the other hand had a higher wing, and a taller two-level cross section, permitting the short NLG.

The above answers the geometric reason.

As for the design choice, fewer blades are more efficient, albeit bigger. As for the nose pitch on ground, it could mean the wing is attached at a lower angle of incidence, permitting a more level floor in cruise.


$^1$ https://www.globalsecurity.org/military/systems/aircraft/l-049-specs.htm
$^2$ http://www.deltamuseum.org/docs/site/aircraft-pages/dc-7_review_booklet_1954.pdf (page 4; PDF page 6)

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    $\begingroup$ Maybe it's just an optical illusion, but there seems to be a huge amount of ground clearance under the Constellation's propeller, compared to the DC-7. $\endgroup$ – David Richerby Apr 11 at 12:59
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    $\begingroup$ @DavidRicherby: That's down to the pitch angle on ground. Lower the nose angle (see the 3-view drawing) and the clearance will go down. What is interesting, is if you visually remove the bay door on the DC-7, it too has a tall NLG. $\endgroup$ – ymb1 Apr 11 at 15:01
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    $\begingroup$ The nose of the DC-7 is also a lot fatter. Give it the same diameter as the Constellation, and you'd wind up with a nose gear almost as long. $\endgroup$ – jamesqf Apr 12 at 1:45
  • $\begingroup$ @DavidRicherby: Be interesting to know if the DC-7 had issues with propeller debris ingestion at soft or gravel fields... $\endgroup$ – Sean Aug 20 at 4:54
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You can see that the underside of the Connie's fuselage ahead of the wing root is contoured upwards to begin the taper which ends at the tip of the plane's nose. The other planes had constant-section fuselages ahead of the wing root, in which the nose does not begin to taper down until just aft of the cockpit.

To maintain the same propeller tip ground clearance, the Lockheed design then required a longer nose gear strut because the attach point for the nose wheel was higher in the air.

(In the case of the Douglas aircraft, maintaining a constant fuselage cross-section forward and aft of the wing reduced tooling costs and enabled fuselage stretches in future revisions of the airframe.)

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