US1476162A - Flying machine - Google Patents

Flying machine Download PDF

Info

Publication number
US1476162A
US1476162A US601608A US60160822A US1476162A US 1476162 A US1476162 A US 1476162A US 601608 A US601608 A US 601608A US 60160822 A US60160822 A US 60160822A US 1476162 A US1476162 A US 1476162A
Authority
US
United States
Prior art keywords
blades
propeller
shaft
casing
pair
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US601608A
Inventor
Lehnert John Alyusious
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US601608A priority Critical patent/US1476162A/en
Application granted granted Critical
Publication of US1476162A publication Critical patent/US1476162A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C11/00Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
    • B64C11/30Blade pitch-changing mechanisms
    • B64C11/32Blade pitch-changing mechanisms mechanical
    • B64C11/34Blade pitch-changing mechanisms mechanical automatic
    • B64C11/346Blade pitch-changing mechanisms mechanical automatic actuated by the centrifugal force or the aerodynamic drag acting on auxiliary masses or surfaces

Definitions

  • This invention relates in general to flying machines, and more particularly to an improvement in the means for propelling, driving or otherwise controlling the flight of such machines.
  • the object of the invention is to provide a propulsion means which may be advantageously utilized for driving or lifting an aero lane or other aeronautical apparatus or or maintaining the lateral stability thereof so that during flight and when landing the machine is under the complete control of the pilot or operator.
  • the invention in its broader aspects consists in providing a propeller carrying one or more propeller blades shiftable-or adjustable so that the pitch of the blades may be varied, controlling means berovided for carrying out the desired in shifting or adjusting of the blades.
  • controlling means berovided for carrying out the desired in shifting or adjusting of the blades.
  • gravity-controlled means such as a pendulum or the like, is organized with the controlling means so that the shifting of the propeller blades is automatically effected under the influence of the pendulum.
  • a pendulum in conjunction with the other elements of the invention whenit is sought to control or preserve the lateral stability of the flyingmachine and in such an organization propellers are provided at each side of the machine and rotate about a vertical axis, the pendulum being so organized with the controlling means for the shiftable propellers that the pitch of the blades of the propeller at the sides of the machine will be automatically regulated to compensate for tilting or other disturbances of the lateral stability of the ship.
  • Figure 1 is a plan view of an embodiment 1 of the invention, parts being broken away and parts being shown in section for the .sake of illustration;
  • Figure 3 is a detail view in elevation of a portion of a propeller blade illustrating the means employed on the propeller blade for adjustably mounting it in the propeller casing;
  • Figure 4 is a view in section on line H of Figure 2.
  • Figure 5 is a view in elevation, showing an aeroplane having the present invention organized therewith insuch manner as to maintain the lateral stability of the plane.
  • the numeral 10 desigates diagrammatically an engine or other power lant from which the propeller shaft 11 is driven by any suitable gearing or motion transmission mechanism.
  • the propeller shaft 11 is squared or of polygonal cross section but intermediate its ends It has fixed thereto a bearing sleeve 12 by which the propellershaft is rotatably mounted in the bearing 13 provided in a frame member 14 suitably associated with the frame of the aeroplane.
  • a propeller casing, designated generally at 15 is mounted: on the outer end of the shaft 11 and is suitably secured to the shaft so as to be held thereon and constrained to rotate with the shaft.
  • This pro eller casing 15 ma be made up of a num er of sections pre erably two, designated at 16 and 17, the sections being bolted to each other in assembly, as at 18.
  • a numberof propeller blades, preferably two, are associated with the casing or frame and are designated at 19 and: 20, respectively.
  • Means are provided for mounting the propeller blades 1n the casing so that these blades are positively constrained to partake of the rotary movement of the casing and shaft while at the same time permitting the blades to be shifted or adjusted about their longitudinal axis to vary the pitch or inclination of the blades
  • This means may comprise caps 21 and 22 bolted or otherwise suitabl secured to the ends of the blades 19 an 20, and each carrying a series of grooved rin the ringsof the ca 21 being designate at 23 and the rings 0 the cap 22 beingdesignated are I a order to prevent accidental or endwise dis-' placement of the blades the caps 21 and 22 are positively connected by a bolt and nut 30 which extends from one cap to the other and through the shaft 11. It is to be understood that the bolt and nut 30 are associated with the caps prior to the assembly of these 7 caps on their respective propeller blades.
  • a two-part. clamp 31 is also provided for positively and directly connecting the blades to the shaft 11, this direct connection bein in addition to the indirect connection which the blades have to the shaft through the propeller casing.
  • the parts of the clamp 31 embrace the shaft 11 and are bolted together by bolts 32 or other suitable fastening means, and this clamp 31 is provided with bearing cavities which receive flanged studs 33 and 34 fixed to the caps 21 and 22, respectively, the studs 33 and 34 being snugly fitted in the bearing cavitiesin the assembly and the flanges of the studs being received in a correspondingly formed part of the bearing cavity to supplement the action of the bolt andnut 30 in preventing endwise or axial displacement of the blade.
  • these studs do not interfere with the shifting or adjusting of the blades about their longitudinal axis since they have working though snug fit in the bearing cavities of the clam Y 31.
  • Shifting mechanism is provided for the blades 19 and 20 and includes a pair of shifting collars 40 and 41 slidably mounted on the shaft 11 exteriorly of the propeller casing.- These collars 40 and 41 rotate with the shaft but are adjustable longitudinally thereon.
  • the collar 40 is rigidly connected with one end of each member of a pair of bars 42, the bars 42 being slidably mounted in longitudinal grooves provided therefor in the shaft 11; These bars- 42 extend through suitable'slots provided therefor in the collar 41, the sleeve 12 and the other elements which are located on the shaft 11* between the collar 40 and a cross head 43 to which the bars 42 are connected at their ends remote from the collar 40.
  • the cross head ed to one end'of each member of a pair of bars slidably received in longitudinal grooves provided therefor in the shaft 11.
  • the grooves which receive the bars 50 are'angularly spaced from the grooves which receive the bars 42.
  • the cross head'53 is mounted for sliding adjustment on the shaft 11 and is arranged in the propeller casing 15 at the inner end thereof.
  • Links 54 and 55 serve to connect .the cross head with crank pins 56 and 57, respectively, the crank pin 56 being mounted on the rings 23 and the crank pin 57 being mounted on the rings 24.
  • the crank pins 56 and 57 are angularly spaced from the crank pins 46 and 47 and preferably are at an angular distance of approximately 90 therefrom. The angular distance which the pinsare spaced from each other ma be varied as may be found desirable.
  • ontrolling means is provided for the shifting mechanism and may comprise a yoke 60 pivotally mounted on a bracket 61 and connected by curved links 62 and 63 to the trunnions of bands or rings 64 and 65 operating in the peripheral grooves of the collars 40 and 41, respectively.
  • a control rod 66 extending from any convenient point of control and susceptible of automatic or manual operation is pivotally connected with the yokeas at 67.
  • the pitch of the blades 19 and 20 of the propeller may be varied as desired irrespective of the rate of rotation of the propeller shaft.
  • the control rod 66 be suitably actuated.
  • this rod 66 may be actuated manually or may be actuated bysuitable automatic mechanism as will hereinafter more fully appear.
  • the rod 66 When the rod 66 is actuated it will move the yoke 60 and if the yoke 60 is moved in the direction indicated by the arrow in Fi ure 2 the yoke will serve in turn to sprea the collars 40 and 41 that is to move these collars away from each other on the shaft, as indicated by thearrows a.
  • the bars 42 and 50 partake of the motion ofthe collars 40 and 41 respectively and transmit the motion of these collars to the cross heads 43 and 53 respectively.
  • the motion of the cross heads 43 and 53 is in turn transmitted to the propeller blades by virtue of the links 44 and 45 and the links 54 and 55, these links coacting with the crank pins as previously described.
  • the propellers being mounted on ball bearings may be readily shifted so as to effect the desired variation in the pitch of the blades but at the same time the propeller blades are positively rotated by the propeller shaft so as to exert the desired driving or lifting effect.
  • FIG 5 the invention is shown organized with an aeroplane so as to maintain the lateral stability thereof and for this purpose a propeller such as. shown in Figures 1 to 4 and previously described is mounted at each side of the plane, the propellers being arranged at each side of the plane and also being arranged to rotate about a vertical axis so that the blades exert a lifting effect.
  • the propellers are designated at 75 and 76 and as they are in all respects identical with the propellers herein above described no detail description is thought to be necessary.
  • the propellers are mounted in any suitable manner upon the framework of the plane which is designated generally at 77.
  • a pendulously mounted ody 80 is provided and is pivotally supported, as at 81, on the framework of the plane.
  • An arm 82 depends from the center to the lower side of this body 80 and this arm 82 is connected by means of rods 83 and 84 to levers 85 and 86 respectively, the levers being also respectively connected to the controlling rods 66 of the propellers 75 and 76 respectively.
  • a propeller shaft a casing mounted on and constrained to rotate with the shaft, a pair of propeller blades, means for mounting the blades on the casing so as to constrain them torotate with the casing while leaving them free to be shifted angularly around their longitudinal axes whereby they vary the pitch pf the blades and shifting mechanism for said blades including a pair of collars slidably mounted on the propeller shaft exteriorly of the casing, a pair of cross heads arranged within the casing, a pair of bars connecting each collar with its crom head, said bars being slidably mounted on the propeller shaft,
  • a propeller shaft a casing mounted on and constrained to rotate with the shaft, a pair of propeller blades, means for mounting the blades on the casing so as to constrain them to rotate with the casing while leaving them free to be shifted angularly around their longitudinal axes whereby they vary the pitch of the blades and shifting mechanism for said blades including a pair of collars slidably mountedv on the propeller shaft exteriorly of the casing, a pair of cross heads arranged within the casing, a pair of bars connecting each collar with its cross head, said bars being slidably mounted on the propeller shaft, a pair of crank pins of op-posite throw carried by each blade, a pair of links between each cross head and the crank pins, the members of each pair of links being connected to its cross head and to the members of the pairs of crank pins on the several blades, and controlling means coopcrating with the collars for simultaneously shifting them in opposite directions on said Shaft.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Description

Dec. 4 1923.
J. A. LEHNERT FLYING MACHINE Filed Nov. -17 1922 I5 Sheets-Sheet 1 8 INVENTOR 5g J.A.Lehned,
ATTORNEYS Dec. 4, 1923. 1,476,162
J. A. LEHNERT FLYING MACHINE Filed Nov. 17, '1922 5 Shets-Sheet 2 INVENTOR John A L e hner'i,
ATTORNEYS Dec. 4 1923.
J. A. LEHNERT FLYING MACHINE Filed Nov. 17, 1922 3 Sheets-Sheet 3 WITNESSES llwflvron Joh'nA; Lqtznetf "AMA . nrrokusys Patented Dec. 4, 1%3.
Maia
OTA.
Farms macnmn a lication filed November 1?, 1922. Serial at. 601,608.
To all whom it may concern:
Be it known that 1, JOHN A. LEHN'ERT, a citizen of the United States, and a resident of Howard, in the State of South Dakota, have invented certain new and useful Improvements in Flying Machines, of which the following is a specification.
This invention relates in general to flying machines, and more particularly to an improvement in the means for propelling, driving or otherwise controlling the flight of such machines.
The object of the invention is to provide a propulsion means which may be advantageously utilized for driving or lifting an aero lane or other aeronautical apparatus or or maintaining the lateral stability thereof so that during flight and when landing the machine is under the complete control of the pilot or operator.
Accordingly the invention in its broader aspects consists in providing a propeller carrying one or more propeller blades shiftable-or adjustable so that the pitch of the blades may be varied, controlling means berovided for carrying out the desired in shifting or adjusting of the blades. In one of the preferred embodiments of the invention gravity-controlled means, such as a pendulum or the like, is organized with the controlling means so that the shifting of the propeller blades is automatically effected under the influence of the pendulum. It is especially desirable to employ a pendulum in conjunction with the other elements of the invention whenit is sought to control or preserve the lateral stability of the flyingmachine and in such an organization propellers are provided at each side of the machine and rotate about a vertical axis, the pendulum being so organized with the controlling means for the shiftable propellers that the pitch of the blades of the propeller at the sides of the machine will be automatically regulated to compensate for tilting or other disturbances of the lateral stability of the ship.
Other objects and advantages of the invention reside in certain novel features of the construction, combination and arrangement of parts which will be hereinafter more fully described and particularly pointed out in the appended claims, reference being had to the accompan in drawings forming part of this speci cation, and in which:
Figure 1 is a plan view of an embodiment 1 of the invention, parts being broken away and parts being shown in section for the .sake of illustration;
and parts being broken away and shown I in section for the sake of illustration;
Figure 3 is a detail view in elevation of a portion of a propeller blade illustrating the means employed on the propeller blade for adjustably mounting it in the propeller casing;
Figure 4 is a view in section on line H of Figure 2; and
Figure 5 is a view in elevation, showing an aeroplane having the present invention organized therewith insuch manner as to maintain the lateral stability of the plane.
Referring to the drawings, and more especially to Figures 1 to 5 the numeral 10 desigates diagrammatically an engine or other power lant from which the propeller shaft 11 is driven by any suitable gearing or motion transmission mechanism. The propeller shaft 11 is squared or of polygonal cross section but intermediate its ends It has fixed thereto a bearing sleeve 12 by which the propellershaft is rotatably mounted in the bearing 13 provided in a frame member 14 suitably associated with the frame of the aeroplane.
A propeller casing, designated generally at 15 is mounted: on the outer end of the shaft 11 and is suitably secured to the shaft so as to be held thereon and constrained to rotate with the shaft. This pro eller casing 15 ma be made up of a num er of sections pre erably two, designated at 16 and 17, the sections being bolted to each other in assembly, as at 18. A numberof propeller blades, preferably two, are associated with the casing or frame and are designated at 19 and: 20, respectively. Means are provided for mounting the propeller blades 1n the casing so that these blades are positively constrained to partake of the rotary movement of the casing and shaft while at the same time permitting the blades to be shifted or adjusted about their longitudinal axis to vary the pitch or inclination of the blades, This means may comprise caps 21 and 22 bolted or otherwise suitabl secured to the ends of the blades 19 an 20, and each carrying a series of grooved rin the ringsof the ca 21 being designate at 23 and the rings 0 the cap 22 beingdesignated are I a order to prevent accidental or endwise dis-' placement of the blades the caps 21 and 22 are positively connected by a bolt and nut 30 which extends from one cap to the other and through the shaft 11. It is to be understood that the bolt and nut 30 are associated with the caps prior to the assembly of these 7 caps on their respective propeller blades.
A two-part. clamp 31 is also provided for positively and directly connecting the blades to the shaft 11, this direct connection bein in addition to the indirect connection which the blades have to the shaft through the propeller casing. The parts of the clamp 31 embrace the shaft 11 and are bolted together by bolts 32 or other suitable fastening means, and this clamp 31 is provided with bearing cavities which receive flanged studs 33 and 34 fixed to the caps 21 and 22, respectively, the studs 33 and 34 being snugly fitted in the bearing cavitiesin the assembly and the flanges of the studs being received in a correspondingly formed part of the bearing cavity to supplement the action of the bolt andnut 30 in preventing endwise or axial displacement of the blade. At the same time these studs do not interfere with the shifting or adjusting of the blades about their longitudinal axis since they have working though snug fit in the bearing cavities of the clam Y 31.
Shifting mechanism is provided for the blades 19 and 20 and includes a pair of shifting collars 40 and 41 slidably mounted on the shaft 11 exteriorly of the propeller casing.- These collars 40 and 41 rotate with the shaft but are adjustable longitudinally thereon. The collar 40 is rigidly connected with one end of each member of a pair of bars 42, the bars 42 being slidably mounted in longitudinal grooves provided therefor in the shaft 11; These bars- 42 extend through suitable'slots provided therefor in the collar 41, the sleeve 12 and the other elements which are located on the shaft 11* between the collar 40 and a cross head 43 to which the bars 42 are connected at their ends remote from the collar 40. The cross head ed to one end'of each member of a pair of bars slidably received in longitudinal grooves provided therefor in the shaft 11. Of course the grooves which receive the bars 50 are'angularly spaced from the grooves which receive the bars 42. I Like the bars 42 the bars 50 extend through openings or slots provided in all the elements which are located on the shaft 11 between the collar 41 and a cross head 53 to which the bars are rigidly connected at their ends remote from the collar 41. The cross head'53 is mounted for sliding adjustment on the shaft 11 and is arranged in the propeller casing 15 at the inner end thereof. Links 54 and 55 serve to connect .the cross head with crank pins 56 and 57, respectively, the crank pin 56 being mounted on the rings 23 and the crank pin 57 being mounted on the rings 24. The crank pins 56 and 57 are angularly spaced from the crank pins 46 and 47 and preferably are at an angular distance of approximately 90 therefrom. The angular distance which the pinsare spaced from each other ma be varied as may be found desirable.
ontrolling means is provided for the shifting mechanism and may comprise a yoke 60 pivotally mounted on a bracket 61 and connected by curved links 62 and 63 to the trunnions of bands or rings 64 and 65 operating in the peripheral grooves of the collars 40 and 41, respectively. A control rod 66 extending from any convenient point of control and susceptible of automatic or manual operation is pivotally connected with the yokeas at 67. With this arrangement the collars may be shifted on the shaft irrespective of whether or not the shaft is rotated since the bands 64 and 65 are loosely fitted in the peripheral grooves of the collars 40 and 41.
l/Vith the invention as thus far described the pitch of the blades 19 and 20 of the propeller may be varied as desired irrespective of the rate of rotation of the propeller shaft. In order to effect variation of the pitch of the propeller blades it is only necessary that the control rod 66 be suitably actuated. As above suggested this rod 66 may be actuated manually or may be actuated bysuitable automatic mechanism as will hereinafter more fully appear. When the rod 66 is actuated it will move the yoke 60 and if the yoke 60 is moved in the direction indicated by the arrow in Fi ure 2 the yoke will serve in turn to sprea the collars 40 and 41 that is to move these collars away from each other on the shaft, as indicated by thearrows a. The bars 42 and 50 partake of the motion ofthe collars 40 and 41 respectively and transmit the motion of these collars to the cross heads 43 and 53 respectively. The motion of the cross heads 43 and 53 is in turn transmitted to the propeller blades by virtue of the links 44 and 45 and the links 54 and 55, these links coacting with the crank pins as previously described. The propellers being mounted on ball bearings may be readily shifted so as to effect the desired variation in the pitch of the blades but at the same time the propeller blades are positively rotated by the propeller shaft so as to exert the desired driving or lifting effect.
In Figure 5 the invention is shown organized with an aeroplane so as to maintain the lateral stability thereof and for this purpose a propeller such as. shown in Figures 1 to 4 and previously described is mounted at each side of the plane, the propellers being arranged at each side of the plane and also being arranged to rotate about a vertical axis so that the blades exert a lifting effect. The propellers are designated at 75 and 76 and as they are in all respects identical with the propellers herein above described no detail description is thought to be necessary.
-The propellers are mounted in any suitable manner upon the framework of the plane which is designated generally at 77. At the center of the plane and intermediate the propellers and 76 a pendulously mounted ody 80 is provided and is pivotally supported, as at 81, on the framework of the plane. An arm 82 depends from the center to the lower side of this body 80 and this arm 82 is connected by means of rods 83 and 84 to levers 85 and 86 respectively, the levers being also respectively connected to the controlling rods 66 of the propellers 75 and 76 respectively.
\Vith this arrangement when the lateral stability of the plane is disturbed the body or frame of the plane will shift relatively of the pendulum 80 and this will effect an adjustment of the controlling rods 66 which will in turn vary thepitch of the propeller blades in the manner herein-above described so as to increase the lifting effect of one propulsion means and decrease the lift' effect of the other pulsion means Where y to overcome the disturbing influence and thus maintain the lateral stability of the plane. This action occurs automatically and occurs as may be necessary to preserve lateral stability. It is to be noted also that by actuating the propeller 66 to the necessary degree that the thrust of the propeller blades may be reversed. This feature is of special advantage in landing or in controlling an airship of the Zeppelin type.
I claim:
I. In a flying machine, a propeller shaft,
a casing mounted on and constrained toro-.
tate with the shaft, propeller blades, means for mounting-the blades on the casing so as to constrain them to rotate with the casing while leaving them free to be shifted to vary their pitch, said mounting means including ing between the caps and having bearingcavities and a flanged stud carried by each cap and received in the adjacent bearing cavities of the clamp.
2. In a flying machine, a propeller shaft, a casing mounted on and constrained to rotate with the shaft, a pair of propeller blades, means for mounting the blades on the casing so as to constrain them torotate with the casing while leaving them free to be shifted angularly around their longitudinal axes whereby they vary the pitch pf the blades and shifting mechanism for said blades including a pair of collars slidably mounted on the propeller shaft exteriorly of the casing, a pair of cross heads arranged within the casing, a pair of bars connecting each collar with its crom head, said bars being slidably mounted on the propeller shaft,
a "pair of crank pins of opposite throw cartween each cross head and the crank pins, the ,members of each pair of links being connected to its cross head and to the members of the pairs of crank pins on the several blades.
3. In a flying machine, a propeller shaft, a casing mounted on and constrained to rotate with the shaft, a pair of propeller blades, means for mounting the blades on the casing so as to constrain them to rotate with the casing while leaving them free to be shifted angularly around their longitudinal axes whereby they vary the pitch of the blades and shifting mechanism for said blades including a pair of collars slidably mountedv on the propeller shaft exteriorly of the casing, a pair of cross heads arranged within the casing, a pair of bars connecting each collar with its cross head, said bars being slidably mounted on the propeller shaft, a pair of crank pins of op-posite throw carried by each blade, a pair of links between each cross head and the crank pins, the members of each pair of links being connected to its cross head and to the members of the pairs of crank pins on the several blades, and controlling means coopcrating with the collars for simultaneously shifting them in opposite directions on said Shaft.
JOHN ALYUSIOUS LEHNERT.
US601608A 1922-11-17 1922-11-17 Flying machine Expired - Lifetime US1476162A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US601608A US1476162A (en) 1922-11-17 1922-11-17 Flying machine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US601608A US1476162A (en) 1922-11-17 1922-11-17 Flying machine

Publications (1)

Publication Number Publication Date
US1476162A true US1476162A (en) 1923-12-04

Family

ID=24408122

Family Applications (1)

Application Number Title Priority Date Filing Date
US601608A Expired - Lifetime US1476162A (en) 1922-11-17 1922-11-17 Flying machine

Country Status (1)

Country Link
US (1) US1476162A (en)

Similar Documents

Publication Publication Date Title
US2428200A (en) Pitch control for aircraft sustaining rotors
US2818123A (en) Rotary wing aircraft
US2653779A (en) Aircraft having reversible jetpropelled rotor blade
US3228479A (en) Rotary wing aircraft
US1476162A (en) Flying machine
US2984306A (en) Helicopter rotor head and its controls
US2410533A (en) Helicopter with coaxial rotors and control means therefor
US1656492A (en) Flying machine
US1788218A (en) Helicopter
US1023233A (en) Flying-machine.
US2497465A (en) Aircraft of the rotary wing type
US1721450A (en) Heavier-than-air flying machine
GB146516A (en) Improvements in and relating to parachutes
US2036923A (en) Aircraft
US1754397A (en) Aeroplane
US1427015A (en) System of aircraft propellers, with blades of variable incidence and cambering
US1310757A (en) letord
US1506716A (en) Helicopter steering and stabilizing mechanism
US1861219A (en) Airplane construction
US2079217A (en) Auto-cyclo-giro
US2161801A (en) Rotary wing aircraft
US1652090A (en) Helicopter
US2001189A (en) Controllable pitch propeller
US1295648A (en) Auxiliary power attachment for aerial navigating-machines.
US1588141A (en) Flying machine