Airplane airframe

DETAILED DESCRIPTION The preferred embodiment of the airplane airframe of the subject invention is comprised of a fuselage 10, wings 12, spars 14 intervening between each wing and the adjacent fuselage section, empennage 16 and wing tip winglets 18.
As can be seen in FIG.
2, the height of each section of each spar 14 is substantially less than the height of the adjacent section of wing 12 and the maximum height of the spar is much less than the maximum height of the wing at its root.
As a result, the non-fuselage generated compression at the intersection of the spar and the fuselage is substantially less than would be encountered if the wing itself joined the fuselage.
It will also be seen that the chord length of the spar is much less than the chord length of the immediately adjacent wing section.
By shortening the chord length the longitudinal distance over which there is increased pressure and smooth airflow disturbance due to the junction is significantly reduced.
This tends to decrease the amount of turbulence and the area over which it acts and hence reduces drag.
Although the drawings show an abrupt change, i.
e.
, a discontinuity in chord length at the spar/wing junction, an alternative embodiment would provide a wing that tapers gradually from the leading and trailing edges to the spar.
Similarly, another embodiment would have the wing thickness taper as it approaches the spar.
The junctions of the spar with the fuselage and with the wing root can be designed to take advantage of the area rule considerations.
In order to withstand the bending and twisting moments at the wing root, the spars must be of substantial strength.
It might therefore be advantageous to use a titanium alloy or some of the more modern composite materials, for example, those which incorporate boron or graphite filaments.
Once again, it should be emphasized that the various features described above can be used independently.
However, the cooperative effects of the combination provide substantial benefits.
For example, employing a lifting body fuselage geometry tends to lessen wing loading and therefore the bending and twisting moments the spars have to withstand