47 is a tube 50, adapted to receive the cable 51 and is secured at
52. The other end of the cable 51 is secured to the link 53, which is
secured to the injection control apparatus by means of a nut 54.
Located below the fuselage and just back of the exhaust pipe
21 is a powerful searchlight 55, so positioned as to permit the dense clouds
of smoke emitting from the exhaust pipe to flow over and around and permitting the beam of
light from the searchlight to be cast upon the dense clouds of smoke while flying thru the
air, regardless of the speed of the plane.
The operation of the apparatus is as follows:
Prior to the operation of the device to produce the meteor or comet effect, while the plane
is in flight, the pump 15 which operates with the engine of the plane, is continuously
drawing the liquid from the tank 11 and directing it to the valve 14. The
needle control valve 18 being normally closed, prevents the flow of the liquid thru
the pipe 17, the pressure thereby opening the ball valve 29 and permitting the
liquid to return to the tank 11 thru the outlet 55 and the pipe 13.
The above described operation insures a complete mixture of the oil or other liquid and any
suitable chemical for producing a smoke effect. If so desired, a chemical may be introduced
for imparting a suitable color to the smoke stream.
Any sulphur dye of reddish tint which would not be decomposed by the heat of the exhaust
pipe would give the smoke a very red glow, or if another color would be desired, such as
green, the use of barium nitrate in finely divided form may be mixed Intimately with the
oil, and when the charge is fired by the exhaust gases the vapor will have a brilliant green
appearance. Similarly, other striking colors may be produced by the selection of suitable
The operator of the plane, while flying, wishing to create a meteor or comet effect,
manipulates the control stick lever 47 which releases the needle control 19
from its seat 35, which allows the liquid to flow thru the small opening 36,
and then thru the passages 44 and 45 into the nozzle 20, and then thru
the jets 39 into the exhaust pipe 21 where it becomes vaporized, and then
passes out of the exhaust opening in the form of a heavy smoke-like vapor to be eventually
illuminated by the rays from the searchlight 55.
The oil pump 15 permits of a high pressure at all times, and is controlled by a relief
valve 14 and a pressure gage 25. The pressure may be adjusted by the pressure
adjusting screw 31.
When the needle control 19 is seated, the flow of the liquid is stopped and as the oil
pump 15 continues to force the liquid thru the pressure regulating valve 14, the
liquid no longer escapes thru the injection valve 18, and a back pressure results,
thereby raising the ball 29 from its seat 28,and so returns thru the passage
56 to pipe 13 and into the liquid tank 11, and at the same time
registers pressure on gage 25.
Calling your attention to the location of the needle control 19, the close proximity
of the needle to the outlet nozzle prevents and eliminates any lag in the shutting off of
the flow of the liquid. Because of the short distance the liquid has to travel before
vaporizing, it allows no ragged stream of smoke to train the main column after the flow has
been cut off. With this clean shut-off, it is possible to write absolutely perfect