- This is a highly-interesting US Navy patent. In the 25
years since this patent was granted, one can only wonder at the advances
and refinements have evolved from this patented delivery system and technology
of creating/spraying chemtrails in the skies above.
- * Note the small particulate sizes cited: from .03 to
- * As the Summary says:
- "Other object, advantages and novel features of
the invention will become apparent from the following detailed description
of the invention..."
- And, at the end of the patent:
- "Other type powder compositions (read: bio/chem
agents) can also be used..."
- "Obviously, many modifications and variations of
the present invention are possible in the light of the above teachings.
It is therefore to be understood that within the scope of the appended
claims the invention may be practiced otherwise than as specifically described."
- * In other words, and to repeat: in the quarter century
since this particular patent was granted, unlimited other applications
and delivery modalities/refinements would be expected to emanate from this
- * Note: The "other patents that reference this patent"
are all blank when clicked...their information is 'not available.'
- Thanks to Chuck Gode in Portland for alerting us to this
patent data...an important clue in the burgeoning chemtrail mystery. -JR
- Werle; Donald K. , Hillside,
- Kasparas; Romas , Riverside,
- Katz; Sidney , Chicago, IL
- The United States of America as represented by the Secretary
of the Navy, Washington, DC News, Profiles, Stocks and More about this
- Issued/Filed Dates: Aug. 12, 1975 / July 22, 1974
- Application Number: US1974000490610
- IPC Class: B64D 1/16;
- Class: Current: 244/136; 040/213; 116/214; 241/005;
- Original: 244/136; 040/213; 116/114.F; 241/005;
- Field of Search: 244/136 040/213 241/5,29 222/3;4 239/171
- R,114 F,114 N,124 R,124 B,124 C
- Legal Status: Gazette date Code Description (remarks)
List all possible codes for US
- Aug. 12, 1975 A Patent
- July 22, 1974 AE Application data
- Light scattering pigment powder particles, surface treated
to minimize inparticle cohesive forces, are dispensed from a jet mill deagglomerator
as separate single particles to produce a powder contrail having maximum
visibility or radiation scattering ability for a given weight material.
- Attorney, Agent, or Firm: Sciascia; Richard S.; St.
Amand; Joseph M.; Primary/Assistant Examiners: Blix; Trygve M.; Kelmachter;
- U.S. References: Show the 1 patent that references this
- Patent Issued Inventor(s)
- US1619183* 3 /1927 Bradner et al.
- US2045865* 6 /1936 Morey
- US2591988* 4 /1952 Willcox
- US3531310 9 /1970 Goodspeed et al. PRODUCTION
OF IMPROVED METAL
- OXIDE PIGMENT
- USR0015771* 2 /1924 Savage
- * some details unavailable
- 1. Contrail generation apparatus for producing a powder
- maximum radiation
- scattering ability for a given weight material, comprising:
- a. an aerodynamic housing;
- b. a jet tube means passing through said housing, said
tube means having an inlet at a forward end of said housing and an exhaust
at a rearward end thereof;
- c. a powder storage means in said housing;
- d. a deagglomeration means also in said housing;
- e. means connecting said powder storage means with said
- means for feeding
- radiation scattering powder from said powder storage
means to said deagglomeration means;
- f. the output of said deagglomeration means dispensing
directly into said jet tube means for
- exhausting deagglomerated powder particles into the atmosphere
to form a contrail; and
- h. means for controlling the flow of said powder from
said storage means to said deagglomeration means.
- 2. Apparatus as in claim 1 wherein said jet tube means
is a ram air jet tube.
- 3. Apparatus as in claim 1 wherein an upstream deflector
baffle is provided at the output of said
- deagglomeration means into said jet tube means to produce
a venturi effect for minimizing back
- pressure on said powder feeding means.
- 4. Apparatus as in claim 1 wherein said deagglomerator
- a. means for subjecting powder particles from said powder
storage means to a hammering action to aerate and precondition the powder;
- b. a jet mill means to further deagglomerate the powder
into separate particles.
- 5. Apparatus as in claim 4 wherein pressurized gas means
is provided for operating said
- deagglomeration means.
- 6. Apparatus as in claim 1 wherein said radiation scattering
- particles are titanium
- dioxide pigment having a median particle size of about
- 7. Apparatus as in claim 1 wherein said radiation scattering
- particles have a coating of extremely fine hydrophobic
colloidal silica thereon to minimize interparticle cohesive forces.
- 8. Apparatus as in claim 1 wherein the formulation of
said powder consists of 85% by weight of
- TiO2 pigment of approximately 0.3 micron media particle
size, 10% by weight of colloidal silica of
- 0.007 micron primary particle size, and 5% by weight
of silica gel having an average particle size of 4.5 microns.
- 9. The method of producing a light radiation scattering
- a. surface treating light scattering powder particles
- interparticle cohesive forces;
- b. deagglomerating said powder particles in two stages
prior to dispensing into a jet tube
- by subjecting said powder particles to a hammering action
in the first stage to aerate and
- precondition the powder, and by passing said powder through
a jet mill in the second stage
- to further deagglomerate the powder;
- c. dispensing the deagglomerated powder from the jet
mill directly into a jet tube for
- exhausting said powder into the atmosphere, thus forming
- 10. A method as in claim 9 wherein said light scattering
powder particles is titanium dioxide pigment.
- 11. A method as in claim 9 wherein said powder particles
are treated with a coating of extremely
- fine hydrophobic colloidal silica to minimize interparticle
- 12. A method as in claim 11 wherein said treated powder
particles are further protected with a silica gel powder.
- The present invention relates to method and apparatus
for contrail generation and the like. An earlier known method in use for
contrail generation involves oil smoke trails produced by injecting liquid
oil directly into the hot jet exhaust of an aircraft target vehicle. The
oil vaporizes and recondenses being the aircraft producing a brilliant
white trail. Oil smoke trail production requires a minimum of equipment;
and, the material is low in cost and readily available. However, oil smoke
requires a heat source to vaporize the liquid oil and not all aircraft
target vehicles, notably towed targets, have such a heat source. Also,
at altitudes above about 25,000 feet oil smoke visibility degrades rapidly.
- The present invention is for a powder generator requiring
no heat source to emit a "contrail" with sufficient visibility
to aid in visual acquisition of an aircraft target vehicle and the like.
The term "contrail" was adopted for convenience in identifying
the visible powder trail of this invention. Aircraft target vehicles are
used to simulate aerial threats for missile tests and often fly at altitudes
between 5,000 and 20,000 feet at speeds of 300 and 400 knots or more. The
present invention is also suitable for use in other aircraft vehicles to
generate contrails or reflective screens for any desired purpose. The powder
contail generator is normally carried on an aircraft in a pod containing
a ram air tube and powder feed hopper. Powder particles, surface treated
to minimize interparticle cohesive forces are fed from the hopper to a
deagglomerator and then to the ram air tube for dispensing as separate
single particles to produce a contrail having maximum visibility for a
given weight material. Other object, advantages and novel features of the
invention will become apparent from the following detailed description
of the invention when considered in conjunction with the accompanying drawing.
- Drawing Descriptions:
- DESCRIPTION OF DRAWING
- FIG. 1 is a schematic sectional side-view of a powder
contrail generator of the present invention.
- DESCRIPTION OF PREFERRED EMBODIMENT
- The powder contail generator in pod 10, shown in FIG.
1, is provided with a powder feed hopper 12 positioned in the center section
of the pod and which feeds a powder 13 to a deagglomerator 14 by means
of screw conveyors 16 across the bottom of the hopper. The deagglomerator
14 produces two stages of action. In the first stage of deagglomeration,
a shaft 18 having projecting radial rods 19 in compartment 20 is rotated
by an air motor 21, or other suitable drive means. The shaft 18 is rotated
at about 10,000 rpm, for example. As powder 13 descends through the first
stage compartment 20 of the deagglomeration chamber, the hammering action
of rotating rods 19 serves to aerate and precondition the powder before
the second stage of deagglomeration takes place in the jet mill section
22. In the jet mill 22, a plurality of radial jets 24 (e.g., six 0.050
inch diamter radial jets) direct nitrogen gas (at e.g., 120 psig) inward
to provide energy for further deagglomeration of the powder. The N2, or
other suitable gas, is provided from storage tanks 25 and 26, for example,
in the pod.
- The jet mill 22 operates in a similar manner to commercial
fluid energy mills except that there is no provision for recirculation
of oversize particles. Tests with the deagglomerator show that at a feed
rate of approximately 11/2 lb/min, treated titanium dioxide powder pigment
is effectively dispersed as single particles with very few agglomerates
- The nitrogen gas stored in cylinder tanks 25 and 26 is
charged to 1800 psig, for example. Two stages of pressure reduction, for
example, by pressure reduction valves 28 and 29, bring the final delivery
pressure at the radial jets 24 and to the air motor 21 to approximately
120 psig. A solenoid valve 30 on the 120 psig line is connected in parallel
with the electric motor 32 which operates the powder feeder screws 16 for
simultaneous starting and running of the powder feed, the air motor and
the jet mill deagglomerator.
- Air enters ram air tube 34 at its entrance 35 and the
exhaust from the jet mill deagglomerator passes directly into the ram air
tube. At the deagglomerator exhaust 36 into ram air tube 34, an upstream
deflector baffle 38 produces a venturi effect which minimizes back pressure
on the powder feed system. The powder is then jetted from the exhaust end
40 of the ram air tube to produce a contrail. A pressure equalization tube,
not shown, can be used to connect the top of the closed hopper 12 to the
deagglomeration chamber 14. A butterfly valve could be provided at the
powder hopper outlet 39 to completely isolate and seal off the powder supply
when not in use. Powder 13 could then be stored in hopper 12 for several
weeks, without danger of picking up excessive moisture, and still be adequately
- Preparation of the light scatter powder 13 is of a critical
importance to production of a powder "contrail" having maximum
visibility for a given weight of material. It is essential that the pigment
powder particles be dispensed as separate single particles rather than
as agglomerates of two or more particles. The powder treatment produces
the most easily dispersed powder through the use of surface treatments
which minimize interparticle cohesive forces. Titanium dioxide pigment
was selected as the primary light scattering material because of its highly
efficient light scattering ability and commercially available pigment grades.
Titanium dioxide pigment (e.g., DuPont R--931) with a median particle size
of about 0.3µ has a high bulk density and is not readily aerosolizable
as a submicron cloud without the consumption of a large amount of deagglomeration
energy. In order to reduce the energy requirement for deagglomeration,
the TiO2 powder is specially treated with a hydrophobic colloidal silica
which coats and separates the individual TiO2 pigment particles. The extremely
fine particulate nature (0.007µ primary particle size) of Cobot S--101
Silanox grade, for example, of colloidal silica minimizes the amount needed
to coat and separate the TiO2 particles, and the hydrophobic surface minimizes
the affinity of the powder for absorbtion of moisture from the atmosphere.
Adsorbed moisture in powders causes liquid bridges at interparticle contacts
and it then becomes necessary to overcome the adsorbed-liquid surface tension
forces as well as the weaker Van der Waals' forces before the particles
can be separated.
- The Silanox treated titanium dioxide pigment is further
protected from the deleterious effects of adsorbed moisture by incorporation
of silica gel. The silica gel preferentially adsorbs water vapor that the
powder may be exposed to after drying and before use. The silica gel used
is a powder product, such as Syloid 65 from the W. R Grace and Co., Davison
Chemical Division, and has an average particle size about 4.5µ and
a large capacity for moisture at low humidities.
- A typical powder composition used is shown in Table 1.
This formulation was blended intimately with a Patterson-Kelley Co. twin
shell dry LB-model LB--2161 with intensifier. Batches of 1500 g were blended
for 15 min. each and packaged in 5-lb cans. The bulk density of the blended
powder is 0.22 g/cc. Since deagglomeration is facilitated by having the
powder bone dry, the powder should be predried before sealing the cans.
In view of long periods (e.g., about 4 months) between powder preparation
and use it is found preferable to spread the powder in a thin layer in
an open container and place in a 400°F over two days before planned
usage. The powder is removed and placed in the hopper about 2 hours before
- Table 1
- CONTRAIL POWDER FORMULATION
- Ingredient % by Weight
- TiO2 (e.g., DuPont R-931)
- median particle size 0.3µ
- Colloidal Silica (e.g., Cabot S-101 Silanox)
- primary particle size 0.007µ
- Silica gel (e.g., Syloid 65)
- average particle size 4.5µ
- Other type powder compositions can also be used with
the apparatus described herein. For example, various powder particles which
reflect electromagnetic radiation can be dispensed as a chaff or the like
from the contrail generator.
- Obviously many modifications and variations of the present
invention are possible in the light of the above teachings. It is therefore
to be understood that within the scope of the appended claims the invention
may be practiced otherwise than as specifically described.
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