Aircraft wheel spray drag alleviator for dual tandem landing gea

Horne, W. B.

English

NASA Technical Reports Server

Feb. 9, 1965 
Filed Dec. 2, 1963 
W. B. HORNE 
AIRCRAFT WHEEL SPRAY DRAG ALLEVIATOR 
4 Sheets-Sheet 1 
L/ 
(NASA CR OR TMX OR AD NUMBER) 
WENTOR 
WALTER B. HORNE 
0 (CODE) 
02 
(CATEGORY) 
https://ntrs.nasa.gov/search.jsp?R=19700027509 2020-03-17T02:13:20+00:00Z
Feb. 9, 1965 W. B. HORNE 3,169,001 
AIRCRAFT WHEEL SPRAY DRAG ALLEVIATOR 
Filed Dec. 2, 1963 3 Sheets-Sheet 2 
lNVENTOR 
WALTER B. MORME 
Feb. 9, 1965 W. B. HORNE 3, E 69,001 
AIRCRAFT WHEEL SPRAY DRAG ALLEVIATOR 
Filed Dec. 2, 1963 4 Sheets-Sheet 3 
FIG. 3 
100 O/o 
FLUID DRAG, LB. 
(WATER DEPTH 2 
= 1.0 INCH) 
0 20 4 0  60 80 
GROUND SPEED, KNOTS 
FIG. 4 INVENTOR 
WALTER 8. HORNE 
ATTORNEYS 
Feb. 9, 1965 W. B, HORNE 3,169,00 k 
AIRCRAFT WHEEL SPRAY DRAG ALLEVIATOR 
Filed Dec. 2, 1963 4 Sheets-Sheet 4 
WITHOUT SPRAY SHIELD 
SLUSH DEPTH, WITH SPRAY SHIELD 
IN. 
0.5 
TAKE-OFF DISTANCE, FT. 
FIG. 5 
INVENTOR 
WALTER B. HORNE 
BY 
ATTORNEYS 
3,169,001 United States Patent Ofice 
,ae .e, , ,, 
3,169,001 
AEWCWAET WHEEL SPRAY DRAG AELEVIATOR 
FVslter B. Morne, Williamsburg, Va., assignor to the 
United Bhtes of America as represented bg the Admin- 
istrator of the Nalioarrrl Aeronautics and Space 
Adantinistiration 
Filed Dec. 2, 1963, Ser, No. 327,555 
11 Claims. (@I. 284-103) 
(Granted under Title 35, U.%, Code (X9521, see. 266) 
The invention described herein mav be manufactured 
wheel bogie landing gear showing the wheel spray drag 
alleviator; 
FIG. 2 is a side elevational view of the dual-tandem 
wheel bogie landing gear partially cut away to reveal the 
connection and location of the wheel spray drag allevi- 
ator: 
FIG. 3 is a rear elevational view of a dual-tandem 
wheel bogie landing gear showing the wheel spray drag 
alleviator; 
FIG. 4 is a graphic view showing fluid drag plotted 
against ground sveed for dual front wheels and for a 
and used by or for the Government of the United States dual-tanzem wheel bogie landing gear with and without 
of America for governmental purposes without the pay- the wheel spray drag alleviator of the present invention; 
ment of any royalties thereon or therefor. and 
This invention relates to a device for alleviating wheel 16 FIG. 5 is a graphic representation of the calculated 
spray drag, and more particularly to an arrangement for runway take-off required for a jet transport in  varying 
alleviating wheel spray drag on landing goar of the four- slush depths with and without the wheel spray drag al- 
wheel bogie type. leviator of the present invention. 
Research has shown that take-off performance of four- Basically, this invention relates to a wheel spray drag 
engine jet transports and other aircraft equipped with 23 alleviator in the form of a deflector. The deflector has 
dual-tandem wheel landing gears is drastically affected by a generally T-shaped cross section, the crest o r  top por- 
the presence of a fluid cover such as slush or water on tion of which is rigidly connected to the wheel support 
runways. Because of this ioss in performance, the one- beam. The deflector is an elongated member extended 
half inch rule is being enforced v~hich prohibits opera- from a position forward of the front wheels and beyond 
tion of jet-turbine comnlercial aircraft from op- 25 the rear wheels. The crest or deflection plate s f  the de- 
erating on runways covered with slush or stznding wa- flector functions to force the spray generated by the 
ter exceeding one-half inch depth. Although prior art wheels downwardly and the dividing or separator plate 
devices have been utilized to prevent fluid drag on the directs the spray away from opposing wheels. 
fuselage of amphibious aircraft, no prior art mechanism Referring now more specifically to  the details of the 
is known which will effectively reduce fluid drag on :O i~vention, FIG. 1 shows a side elevational view of the 
wheels of aircraft landing gear. landing gear bogie designated generally by the reference 
The wheel spray drag alleviaior disclosed herein has numeral 80. 
proven in numerous tests that the fluid drag may be re- The bogie 10 includes a main strut I2 which may be 
duced as much as forty-four percent on a four-wheel of a conventional tubular design. Fixed to the main 
bogie type landing gear. This is accomplished by de- 33 strut 12 is a wheel support beam 14. The beam 14 is 
flector plates connected to the bogie landing gear in  such located in a plane substantially perpendicular to the main 
manner that the front wheel fluid spray is prevented from strut $12 and extends from either side thereof. Axles 
impinging on the rear wheels of such landing gear, and 15 and 16 are carried by the beam 14 forward and aft 
thus results in a substantial reduction of fluid drag on of the nuin strut 12 in a conventional manner. Wheels 
the gear system. 40 23 and 21 are journaled on the axle 15 and wheels 19 
I t  is therefore, an object of this invention to provide and 20 on the axle 16. This is all conventional structure 
a wheel spray drag alleviator which will effectively re- constituting a dual-tandem wheel bogie landing gear 
duce fluid drag generated by the landing gear wheels. which might be found on a large jet aircraft o r  other air 
Another object of the invention is to provide a wheel vehicles. 
spray drag alleviator vyhich is adapted for use with dual- 45 Connectors or brackets (FIG. 2) 24 and 25 are fixed 
tandem wheel landing gears. to the bottom of the wheel support beam 14 in a well 
A further object of the invention is to provide a wheel known manner such as by bolts or welding. The deflec- 
spray drag alleviator which will allow aircraft to safely tor 28 is in turn fixed to the bottom of the brackets 24 
operate on a runway covered with slush or water exceed- and 26 by a conventional fastening technique such as 
ing one-half inch depth. 50 welding, riveting, or securing with bolts. 
Still another object of the invention is to provide a The deflector 28 consists of a crescent-shaped crest 
wheel spray drag alleviator whiih will increase aircraft or deflector plate 30 (FIG. 3)  and a dividing or separat- 
take-off acceleration and performance on runways cov- ing plate 32. The deflection plate and separator plate 
ered with slush or standing water. are of a length such that portions project forward of the 
Yet another object of the invention is to provide a 55 front wheels 18 and 211 and beyond the rear wheels 19 
wheel spray drag alleviator which has a minimum effect and 20. The plates when joined together have a generally 
on the aelodynamic characteristics of an aircraft. T-sha2ed cross section as illustrated in  FIG. 3. The de- 
Another object of the invention is to provide a wheel flection plate 30 and separator plate 32 may be secured 
spray drag alleviator whish is of simple design, economi- together by known techniques. The deflector plate may 
cal to rnanufaclure, easy to install and maintain, and re- 60 be constructed from various materials, but should have 
liable under adverse runway conditions. a rigidity sufficient to withstand the forces of the fluid 
An additional object of the invention is io plovide an spray generated by the wheels. I t  has been found that 
aircraft landing arrangement which will improve passen- the separator plate 32 may be constructed of a flexible 
ger safety. material since the spray generated by the adjacent wheels 
Yet another object of the invention is to provide a G5 provides a force on either side thereof which is approxi- 
spray drag alleviator which can be readily attached or mately equal, any resultant force being relatively small 
detached as the weather and seasons control its necessity. to substantially zero. 
These and other objects and advantages of the inven- As shown in FIGS. 1 through 3, deflector 28 is lo- 
tion will become more appa~ent upon reading the speci- cated below the axis of rotation of the wheels and in a 
fication in conjunction with tlle accompanying drawings. 70 position essentially parallel to wheel support beam 14. 
In the drawings: Deflector plate 28 is of sufficient width dimension such 
FIG. 1 is a side elevational view of a dual-tandem that it lies adjacent the wheels preventing the majority 
3,109,OCml 
3 
C" 4 
of the spray from bypassing the deflector plate. The design, the deflector can be seasonally addcd or removed 
spray pattern from the front wheels of a bogie gear sys- from the aircraft as weather conditions so dictate. 
tem, when passing through slush, is similar to that 05- As illustrated by the calcualted resu!ts shown in FIG. 
served as the wake of any object, for example a boat, 5, the advanta~es of the present inveniion regarding pas- 
rfloving though water. More specifically, the spray Pat- 5 senger safcty are readily apparent. Fcr examp!e, when 
tern is essentia!ly divided into outwardly and inrnard!~ exp!oying the deflector zs taught by the present invention 
directed portions each in an initial slight upward direc- take-off distance required for a jet transport in two 
tion. The outwaidly directed portion of this pattern pre- inches of slush is withill the limits of most runways while, 
sents no real problem, but portions of the inwardly di- without this invention, take-off in this amount of slush 
rected spray tend to impinge on the rear wheels and re- 10 requires an infinite length and would be impossible. This 
sd t s  in substantial drag on a conventional bogie-type reduced take-off distance ~ b ~ ~ i o u ~ l ~  serves to promote pas- 
system. The novel deflector of the present invention also senger sale:y, even when applying the present "one-half 
suppresses the so-called "rooster-bail" effect, i.e., the Spray inch rule," and permits required military take-offs to be 
pattern normally displayed by converging portions of the performed more safely. 
inwardly directed spray as produced by dual wheels, 15 While a preferred embodiment of this invention has 
which normally tends to move upward from the point of been &scribed, it will be understood that modifications 
convergence to strike other parts of the aircraft and and improvements may be made thereto. Such of these 
thereby contribute to drag during aircraft take-off in n1odifications and improvements as incorporate the prin- 
slush. ciples of this invention are to be considered as included 
As apparent from FIG. 3 of the drawings, when utiliz- 29 in the hereinafter appended claims unless these claims 
ing the present invention, the inwardly directed spray will by their language expressly state otherwise. 
be prevented from reaching the rear wheels of the bogie What is claimed as new and desired to be secured I:y 
system by deflector plate 368 and separating plate 32. Letters Patent of the united States is: 
Thus, separator plate 32 operates as a spray divider and 1. A device for reducing fluid drag on a vehicle travel- 
prevents, for example, spray from the front wheels 1% and 5 5  ing on a slushy or rain-covered ruilway comprising: 3 
21 from impinging on rear whee!s 20 and 19, respec- vehicle; a wheel support beam associated with said ve- 
lively, while also preventing spray from the tandem l-ticle; at least one wheel suppo~ted by tke Seam; and de- 
wheels 18 and 19 from impinging on the tandem wheels Rection means carried by said support beam and located 
20 and 21 and vice versa. adjacent said wheel in a position to deflect spray gen- 
Although the deflector 28 is ~~~~~j;in as an elongated 30 erated by said wheel away from said vehicle and from 
member having a generally Y-shaped cross section, it is redirecting spray onto said wheel whereby fiuid drag 
to be understood that within the broadest aspects of the is reduced. 
invention the deflector plate may take various sizes and 2. A device for reducing fluid drag on a vehicle travel- 
configurations as deemed necessary to meet the require- ing on a slushy or rain-covered runway comprising: a 
ments of a particular dual-tandem wheel bogie landing 25 vehicle; a wheel support beam associated with said ve- 
gear arrangement. For example, due to the increasing hicle; at least one wheel supported by the beam; and 
aircraft speed during roll through slush on take-0% the deflection means carried by said vehicle and located ad- 
majority of the inwardly directed spray from the wheels jxent  said wheel to deflect spray generated thereby; said 
will be channeled rearward of the gear system by divider deflection means having a shape and being positioned sub- 
32 without ever reaching deflecior plate 30. Thus, the 40 stantially parallel to the surface over which the vehicle is 
deflector could take a generally V-shaped or U-shaped running, below the axis of rotation of the wheel and in 
cross sectional configuration and be segmented rather than a manner to deflect spray generated by said wheel away 
a continuous elongated member, as examples of possible from said vehicle and from redirecting spray onto said 
modifications. Other means of supporting the deflecior wheel. 
may be utilized, as well as the deflector assuming other 45 3. A device for reducing fluid drag on an aircraft bogie 
positions and locations and still be considered within the landing gear traveling on a slushy or rain-covered run- 
scope of the invention. A!though the deflector is de- way comprising: A main strut adapted to be connected to 
signed particularly for use with a dual-tandem wheel an air vehicle body; a support beam carried by said sirut; 
bogie for aircraft, it would have application to other tandem wheels rotatably mounted on said support beam; 
landing gear arrangements as well as to vehicles other 50 deflection means having a shape and being located ad- 
than aircraft. jacent said tandem wheels in a position whereby fluid 
The graphical representation shown in FIG. 4 of the spray thrown by one of said wheels is prevented from 
drawings clearly illustrates that use of the deflector greatly impinging against the vehicle, another of said wheels; 
reduces the fluid drag. As shown herein, taking the or being redirected onto said one of said wheels thereby 
conventional bogie assembly without the drag alleviator 55 alleviating fluid drag. 
of the present invention as one hundred percent (as rep- 4. A device for reducing fluid drag on an aircraft boaie 
resented by the solid line), the maximum drag for the landing gear traveling on a slushy or rain-covered run- 
system is reduced to 55.9 percent when utilizing the herein way as in claim 3 wherein said deflection means is an elon- 
described alleviator under like conditions (as repre- gated member extending adjacent at least two wheels 
sented by the lower dotted line). Thus, the entire bogie 60 of said tandem arrangement. 
system is subjected to less drag when using the present 5. A device for reducing fluid drag on an aircraft bogie 
alleviator than that experienced by the front wheels of landing gear traveling on a slushy or rain-covered runway 
this type systen~ alone without the use of the present in- as in clairil 3 wherein said deflection means is an elon- 
vention (note the center broken line on FIG. 4). This gated member extending adjacent at least two wheels of 
obvious advantageous feature of the present invention is 65 said tandem arrangement; and said elongated member 
particularly evident in the high speed range of sixty to having a section for directing fluid spray downwardly and 
one hundred knots, and ';ligher, where take-off accelera- another section for directing spray away from itself. 
tion and performance is most critical for large aircraft. 6. A device for reducing fluid drag on an aircraft bogie 
Other advantages of the present invention include the landing gear traveling on a slushy or rain-covered run- 
simple and economical design of the deflector. That is, 70 way as in claim 3 wherein said tandem wheels include at 
there are no moving parts and it is therefore extremely least dual-tandem wheels; and said deflection means being 
In addition, the deflector can be made of very an elongated member extending between said dual-tan- 
lightweight metal, plastics, neoprene or like materials dem wheels. 
and therefore adds little penalty to the payload capability 7. A device for reducing fluid drag on an aircraft bogie 
of the aircraft. Furthermore, dl;e to the simplicity of 75 landing gear traveling on a slushy or rain-coveied runway 
3,169,001 
5 6 
as in claim 3 wherein said tandem wheels include at least stantially parallel to the surface over which the vehicle 
dual-tandem wheels; said deflection means being located is running and below the axis of rotation of the wheels. 
between said dual-tandem wheels; and said deflection 10. A device for reducing fluid drag on an aircraft 
means having a portion for directing fluid spray down- bogie gear traveling on a slushy or rain-covered runway 
wardly and another portion for directing fluid spray 5 comprising: a main strut adapted to be connected to an 
outwardly; said last mentioned portion also separating air vehicle body; a support beam carried by said strut; 
fluid generated by adjacent dual wheels. tandem wheels rotatably mounted on said support beam; 
8. A device for reducing fluid drag on an aircraft bogie deflection means located adjacent said tandem wheels; 
landing gear traveling on a slushy or rain-covered run- said tandem wheels include at least dual-tandem wheels, 
way comprising: a main strut adapted to be connected 10 said deflection means being an elongated plate located 
t o  an air vehicle body; a support bean1 carried by said between said tandem wheel pairs and extending forward 
strut; tandem wheels rotatably mounted on said support of, in one direction and beyond said wheels in the other 
beam; deflection means located adjacent said tandem direction; said elongated member having a generally T- 
wheels; said tandem wheels include at least dual-tandem shaped cross section and being positioned substantially 
wheels, said deflection means being an elongated plate 15 parallel to the surface over which the vehicle is running 
located between said dual-tandem wheels and extending at a location below the axis of rotation of the wheels. 
forward of, in one direction, and beyond said wheels 11. A device for reducing fluid drag on an aircraft 
in  the other direction; and said elongated member having bogie gear traveling on a slushy or rain-covered runway 
a section directing fluid spray downwardly and a section as in claim 7 wherein said last-mentioned portion is 
directing spray outwardly; said section directing spray 20 flexible. 
outwardly also separating spray from adjacent dual 
wheels. References Cited by the Examiner 
9. Adevice for reducing fluid drag on an aircraft bogie UNITED STATES PATENTS 
gear traveling on a slushy or rain-covered runway corn- 2,038,234 4/36 Olen ------- 280-154.5 
prising: a main strut adapted to be connected to an air 25 2 080 161 5/37 B~~~~~~~ -------- 280-154.5 x , I vehicle body; a support beam carried by said strut; tan- 2,572,342 10/51 Huett - ---_----------- 244-100 
dem wheels rotatably mounted on said support beam; 
defIection means located adjacent said tandem wheels; FOREIGN PATENTS 
said tandem wheels include at least dual-tandem wheels, 3 1,209 1/23 Denmark. 
said deflection means being an elongated plate located 30 373,569 5/32 Great Britain. 
between said dual-tandem wheels and extending forward 
of, in one direction, and beyond said wheels in the other BUCHLERy Prinzary Examiner' 
direction; and said deflection means being positioned sub- ANDREW H. FARRELL, Examiner. 


Aircraft wheel spray drag alleviator Patent

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