Buoy launch container extender

A launch-chute extender is disclosed that snap-fits onto the end of a buoy ontainer in an aircraft that carries stores internally. This extender, by adding its tubular configuration to the end of the buoy container, provides guiding clearance to selected stores to enable them to exit from the underside of the aircraft without becoming jammed.

BACKGROUND OF THE INVENTION 
The instant invention relates to the devices on-board an aircraft that 
allow the physical passing of an object through the aircraft belly, such 
as a cylindrical tube, from a position inside the craft to one outside. 
In many instances, when aircraft are patrolling the oceans, it may be 
necessary to launch objects, such as sonobuoys or flares, from an inner 
compartment, through the aircraft's underside skin, to the outside. Some 
aircraft are fitted with a internal pressurized launch chutes that extend 
from just inside the cabin area to a position adjacent to the inside of 
the aircraft skin. A mechanically-operated door, acting in place of the 
skin, moveably covers and uncovers the opening and allows the object to be 
fired by either hydraulic or pneumatic means, into the surrounding 
atmosphere. 
Of course, during this time, the aircraft is flying at a predetermined 
altitude and airspeed and there can be quite a lot of turbulent airflow 
adjacent the aircraft's skin or within the area adjacent the ends of the 
launch tubes. In designing the area to hold the launch chutes, a selected 
amount of space between the mechanical door and the end of a launch 
container was chosen to aid in the construction of the aircraft. At the 
time of aircraft design, the approximate size of the buoy, such as a 
sonobuoy, was known (it was a 3 foot long tubular object) and it was 
determined that this size would launch without difficulty. The container 
was long enough so that as the lead end of a buoy started into the cavity 
between the aircraft skin and the end of the container, the trailing end 
of the buoy was still positioned in the launch container, thus ensuring 
that the total length of the buoy would not be jostled out of position and 
would pass on through without mishap. As times progressed, the size of the 
sonobuoy decreased to a point where the buoy was now physically small 
enough so that it could get caught inside the cavity space. If this event 
occurred, the automatic cover over that particular launch chute could be 
prevented from closing and the cover-motor could even burn out. This left 
a very undesirable flight condition. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide a means to 
facilitate the launching of smaller-sized objects from an aircraft's 
automatic launch tubes. 
It is another object of the present invention to facilitate the launching 
with the least costly means possible. 
It is still another object of the present invention to provide a means to 
facilitate the launching of a buoy that can be integrated into existing 
equipment without requiring extensive modification thereof. 
These and other objects and many attendant advantages of the present 
invention are obtained where a tubular, launch chute extender is available 
to "snap lock" onto the base of an individual launch container that is 
fitted inside a launch chute in an aircraft. At the inner-most end of the 
extender, at least two spring-tensioned lugs extend beyond the rim and 
snap into specially-shaped apertures located in appropriate places near 
the end of a launch container. In addition, the rim of the extender has a 
plurality of stabilizing protrusions extending therefrom to mate with 
similarly-shaped cavities in the end of the container. Finally, at the 
opposite, discharge end of the extender, the rim has been bevelled to 
allow clearance for the moving cover while still providing guidance to the 
moving buoy.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
As technology has progressed, achievements in the electronics industry have 
allowed the miniaturization of many parts or objects used by the services, 
such as sonobouys. Although the downsizing of the buoys has been achieved, 
a similar change in the size of the functional, associated equipment was 
not undertaken. This meant that in some cases, the sections of the 
aircraft used to carry and launch the buoys, when the much smaller buoys 
were to be used, were physically too large to do the job properly. 
Referring now to the drawings, wherein like reference characters designate 
like or corresponding parts throughout the several views, FIG. 1 shows a 
perspective view of the area 12 of the underside an aircraft 10 where 
small sonobuoys or flares are launched from. FIG. 2 shows a plan view of 
this area 12, as taken from underneath the aircraft 10, and FIG. 3 shows a 
partially fragmented cross-sectional view of area 12, taken along the 
length of aircraft 10, showing a plurality of aircraft launch chutes 14 
with buoy launch containers 16 therein. Prior to flight, individual buoys 
18 (see FIG. 4) are loaded into containers 16 and they are secured in 
launch chutes 14. 
FIG. 4 shows an isolated cross-sectional view of one of the launch 
containers 16 with the instant invention, a launch tube extender 20, 
attached. FIG. 5 is a cross-sectional view, taken along lines V-V of FIG. 
4, of the junction of extender 20 to the outboard edge of launch container 
16 and FIG. 6 shows an expanded perspective view of extender 20 as it is 
attached to the end of launch container 16. 
As seen more clearly in FIG. 6, extender 20 is a tubular piece having an 
inwardly extending end 24 and an outwardly extending end 44. The rim 26 of 
inner end 24 has four rectangular-shaped, alignment tabs 28a-d extending 
therefrom off the edge of extender 20 in an axial direction to mate with 
corresponding openings 15a-d, respectively, (only 15a and 15b shown in 
FIG. 6) in the lower end of container 16. Extending from immediately 
adjacent rim 26 longitudinally throughout the full length of the extender 
is a slot 32, that allows extender 20 to fit over a protrusion in the 
aircraft (not shown in FIG. 6) Slot 32 is formed by removal of tube 
material around an arc of between 60 and 65 degrees centered on the 
extender's maximum longitudinal axis. Extender 20 also has a pair of 
elongated snap lugs 34a,34b positioned diametrically opposite one another 
and imbedded into the surface of inward end 24. Lugs 34a,b are formed from 
flexible elongated strips of hardened aluminum that, at one end, are 
fastened, such as by sheet metal screws, or other suitable fasteners, 35 
to the sides of extender, and at the other ends, have small hooks or 
flanges 36a,36b, respectively. Flanges 36a,b are constructed to "snap-fit" 
into appropriately-sized apertures 38a,38b cut in the bottom end of launch 
container 16. Outwardly-extending end 44 is beveled to a bias cut to allow 
clearance when aircraft door 46 (seen in phantom in FIG. 4) swings open. 
Extender 20 is designed to be installed onto the end of launch container 16 
before the container is loaded onto an aircraft. The fit of extender 20 
when sealed onto a launch container 16 must not exceed the outside 
diameter of container 16. When a buoy is fired, after the aircraft door is 
opened, it is guided from the end of container 16, through extender 20, 
out of the aircraft and into the airstream without finding space for 
jamming. Extender 20 can be designed to be taken off of an empty container 
16 and reused or be disposed of when the container is discarded. 
Finally, while the chute extender has been described with reference to a 
particular embodiment, it should be understood that the embodiment is 
merely illustrative as there are numerous variations and modifications 
which may be made by those skilled in the art. Thus, the invention is to 
be construed as being limited only by the spirit and scope of the appended 
claims.