DE3412371A1 - Boundary-layer suction without motor-driven units for winged aircraft - Google Patents

Abstract

An aircraft according to the patent application is an amalgamation, without any compromises, of a fast aircraft and a very slow aircraft, as becomes evident from the four claims and the description. In the case of a very small aircraft, a speed ratio of even 10:1 is possible, as a 2m model built in 1940 showed, in 1941, with a ratio of 371:37 kph (anti-aircraft gun observer, West Cologne). 1.) The reduced-pressure flow does not separate. Where a conventional aircraft reaches the critical speed immediately before landing, it must land! At this time, an aircraft according to the patent application still has somewhat more than three times the lift! That is not all. In addition: 2.) Increase in the wing area by virtually 50%! 3.) A higher angle of attack is possible, because there is no longer any critical speed. The advantages of a landing path reduced by 70-80%, that is to say to approximately a quarter, are self-evident. However, with less than 6 seats, the cost is too great, and four-seater aircraft uneconomically rarely have a landing speed over 100 kph. The limit is difficult to draw here, since a six-seater aircraft with suction manages even at around 50 to 60 kph. This category would be the highlight in the "third world", and primarily in Canada, up to the shuttle, as recognised specialists have told me.

Description

Boundary layer extraction without motor-driven units

for hydrofoil airplanes D e ctio n of a hydrofoil airplane, equipped according to the four mutually dependent claims. Sheet 1 All hydrofoil aircraft have a "critical speed at which the negative pressure flow above the Wings tear off, which means that a little more than two thirds of the lift is lost. this to prevent is the purpose of the invention.

£: 5 Nowhere is anything known that suction on any Wise, not even with motor-driven pumps or fans, over a large area could be realized, except in small subareas; the critical speed could only be reduced somewhat, like the many test aircraft, mainly in the USA, ice; but the break in the negative pressure flow stayed with your high and such dangerous loss of buoyancy exist, as the accident statistics show.

With a system for wings according to the invention it looks different, because the upper profile planking is made permeable to more than 50% by means of small slits is. Underneath is the planking that seals against the interior of the wing and is connected to the permeable upper planking forms a pocket that widens towards the trailing edge of the wing and closed at the bottom by a curved flap, the flap.

The latter opens @ at the same time as the landing flaps are extended (Fig.1). It deflects the gap flow of the dynamic pressure between the landing flap nose and wing lower Boundary layer suction without motorized Aggregates for hydrofoil aircraft E s c h r e i b u n 5 smooth 2 (lower wing) Page passes through at high speed, sharply downward, directed slightly obliquely on the back of the landing flaps, so that even with these the negative pressure flow below critical speed as with one in normal flight attitude Wing is preserved. This creates the negative pressure area sucking out of the pocket greatly expanded behind the flap. Easing of the negative pressure flow over the wing is no longer possible, the critical speed is hereby eliminated.

Unfortunately, this shifts the center of lift to the rear, the plane is top-heavy. In this case, only one wing can be of maximum extension balance the front over the profile; because the normal elevator has, as is well known hardly any effect if the flight is too slow.

The slat, a section, takes over this lift from the wing nose (A 2, Fig. 2). It even works when fully extended against the stop increasing 3ahnflug. It can, although extended at the same time as the other flaps, be pulled back a little via its suspension until it is released by the front additional lift brings the aircraft into orbit flight! So that is Control option before landing far below the (without my) principle) critical Speed ensured with completely ineffective elevator.

The effect of this principle of boundary layer suction, negative pressure flow application and center of lift - the possibility of displacement would hardly be half use if the Boundary layer extraction without motorized units For Hydrofoil Airplanes B a s h r e i n g e Sheet 3 (the) flap system including: Slats would not extend over the entire wingspan. With that they fall usual ailerons completely gone, but not elevator and rudder for cruising flight. A replacement for ailerons must be able to change position around the longitudinal axis as well provide. That is with reciprocating airbrakes à la glider itself not possible for the best pilot. Therefore the "saw" (Fig.3), which can be lifted alternately, progressive, the very finest change in position or course enables up to sharper Curve initiation. But even this aileron replacement works even if it is oversized no longer with the slowest landing possibility of this system. Therefore must for safe control of a landing in the case of a gusty etter in the shortest possible space - multiple Effect enhancement can be provided: The hollow aileron (Fig. 4), which is used during cruise would have a devastating effect. For this reason it is placed in front of the "saw" unW locked in flight without flaps.

The lock is only lifted when the flaps and slats are up are extended to the stop. Only after the gentle introductory has been fully extended Aileron "saw" (Fig.3) to the end position begins the function of the hollow aileron.

- L e r s e i t e -

Claims (4)

Boundary layer extraction without motor-driven units, for hydrofoil aircraft Main claim (1): Grenzschidtabsaugung without motorized units for Hydrofoil aircraft, characterized in that a due to the dynamic pressure under The high-speed fissure flow generated by the wing, primarily between them Underside of the wing and nose of the extended as part of the underside of the wing (double) Turn the flap down sharply to open the flap deflected at the bottom, hitting the back of the flaps, thus behind the flap system and forming a strong negative pressure area in front of the trailing edge of the wing, through which Interior of the pocket equal to strong negative pressure because of the boundary layer and more sucks in above the sash through the holes or slots in the upper profile planking and thus applies the current when the object becomes too slow. 2. Slat, characterized in that it is a voraerer upper part of any wing profile, starting from the pressure point of the respective profile at the critical angle of attack of the fixed wing aircraft, until just before the point of Reaching the greatest wing thickness, as an independent second wing of shallow depth and thus very large elongation appears, which when lifting - solution from the Profii - Un storage at the back (lifting up in front) with ### the remaining one Main wing in cross-section one. forms funnel-shaped opening. 3, ailerons for maximum speed, characterized in that in the north: near the greatest profile thickness transversely to the flight direction in a wing section, on the outside, a thin profile closing strip, attached to the tips a saw-like plate, liftable, exclusively from the start of the extension Flow turbulence generates up to the destruction of the re-building boundary layer suction after taking back the rudder. 4. Ailerons for slowest locomotion, characterized in that that there is a depression in the upper side near the greatest thickness of the wing, the profile is finally covered by a short rotatable wing piece, which rotatable up to the vertical to the profile, by means of the jam, which is partly due to the corresponding hollow shape behind this rudder wing blown against the upper flow lowers the wing of the aircraft and brakes.