US008O15795B2

(12) United States Patent (10) Patent No.: US 8,015,795 B2

(54) AIRCRAFT COMBINATION ENGINES (52) U.S. Cl. ................. 60/224; 60/225; 60/782; 60/785
PLURAL AIRFLOW CONVEYANCES (58) Field of Classification Search .................... 60/224,
SYSTEM 60/225,782,785
See application file for complete search history.
(75) Inventors: Frederick M. Schwarz, Glastonbury,
CT (US); Brian M. Fentress, (56) References Cited
Marlborough, CT (US)
U.S. PATENT DOCUMENTS
(73) Assignee: United Technologies Corporation, 7,690,188 B2 * 4/2010 Schwarz et al. ................ 60,224
Hartford, CT (US) 7,690,189 B2 * 4/2010 Schwarz et al. ................ 60,224
7,743,613 B2 * 6/2010 Lee et al. ........................ 60,782
(*) Notice: Subject to any disclaimer, the term of this * cited by examiner
patent is extended or adjusted under 35
U.S.C. 154(b) by 1374 days. Primary Examiner — Michael Cuff
This patent is subject to a terminal dis- Assistant Examiner Craig Kim
claimer. (74) Attorney, Agent, or Firm — Kinney & Lange, PA.
(21) Appl. No.: 11/804,429 (57) ABSTRACT
An engine combination for generating forces with a gas tur
(22) Filed: May 18, 2007 bine engine generating force, and an internal combustion
(65) Prior Publication Data engine provided in the combination as an intermittent com
busti
ustion engine generating force having an air intake, there
US 201O/OO13242 A1 Jan. 21, 2010 being a plurality of air transfer ducts each extending from a
different location in the gas turbine engine so as to be capable
(51) Int. Cl. to provide air in each of those air transfer ducts at one end
FO2K 3/00 (2006.01) thereofat pressures differing from one another and connected
FO2K 700 (2006.01) at the other end of each to the air intake to transfer air thereto.
FO2K9/00 (2006.01)
FO2K 99/00 (2006.01) 22 Claims, 1 Drawing Sheet

14
U.S. Patent Sep. 13, 2011 US 8,015,795 B2

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 US 8,015,795 B2
1. 2
AIRCRAFT COMBINATION ENGINES can operate with a fuel efficiency on the order of seventy
PLURAL AIRFLOW CONVEYANCES percent (70%) better than that of a continuous combustion
SYSTEM (Brayton cycle) internal combustion gas turbine engine. At
high altitudes, internal combustion engines of all kinds face
CROSS-REFERENCE TO RELATED the possibility of limited power output because of the rela
APPLICATION tively small air pressures there limiting the chemical reactions
of oxygen with hydrogen and oxygen with carbon in the
Referenced herein is U.S. application Ser. No. 1 1/713,262 burning of the engine fuel in the engine combustion chamber
filed Mar. 2, 2007 for “COMBINATION ENGINES FOR or chambers. This can be solved for gas turbine engines by
AIRCRAFT by Frederick M. Schwarz, Brian M. Fentress, 10 providing therein very large air flows through use, typically,
Andrew P. Berryann, Charles E. Lents and Jorn A. Glahn. of axial flow compressors usually in two stages with both a
low compression compressor followed along the fluid flow
BACKGROUND OF THE INVENTION path through the engine by a high compression compressor.
This arrangement provides at least enough compressed air to
The present invention relates to gas turbine engines for 15 the Subsequent combustor to Sustain the desired combustion
aircraft and, more particularly, to gas turbine engines each process therein and a mass of airflow Sufficient to combine
coupled to a corresponding auxiliary engine. with enough fuel to provide the energy needed to overcome
Gasturbine engines as continuous combustion, open Bray the aircraft drag at the speed and altitude intended for opera
ton cycle internal combustion engines have come to dominate tion.
as the power plants for larger, faster aircraft to essentially the However, Such compressors can provide considerably
exclusion of reciprocating engines, or internal, intermittent more compressed air than the minimum needed for this pur
combustion engines, earlier used as power plants for these pose thereby allowing some of this compressed air to be
kinds of aircraft. This is largely because of the greater power delivered through an air transport duct to the air intake of an
to-weight ratio of gas turbine engines versus internal com intermittent combustion internal combustion engine so that,
bustion engines, especially in large horsepower engines, or, 25 in effect, the compressors of the gas turbine engine serve as a
more appropriately, large thrust engines in which those large very capable Supercharger for that intermittent combustion
thrusts are provided with a relatively small, and so smaller engine. Thus, this intermittent combustion engine can be
drag, frontal area engine structures relative to reciprocating operated at the same relatively high altitudes at which the gas
engines. Gas turbine engines generate such large thrusts for turbine engine propelling the aircraft operates while this tur
propulsion, or horsepower for engines with an output shaft, 30 bine engine is also supplying compressed air to that intermit
by combining large Volumes of air with large amounts of fuel, tent combustion engine. There, depending on the values
and thereby form a jet of large velocity leading to the capa selected for the peak air intake pressure and engine compres
bility to provide desired speedy flights. sion ratio, the intermittent combustion engine can be used as
In addition to providing thrust, such gas turbine engines a power source for an electrical power generator that can
have operated integrated drive generators to generate electric 35 generate much greater amounts of electrical power than can
ity for the aircraft and for the engine electronic controls. The one powered by a gas turbine engine.
amount of electricity needed for these purposes in the past has In Such aircraft so equipped with a gas turbine engine used
tended to be relatively modest typically in the range of a few as a Supercharger for an accompanying intermittent combus
hundred kilowatts of electrical power but, with recently arriv tion engine while also propelling the aircraft, the amount of
ing new aircraft, exceeding a megawatt of power. However, 40 electrical power needed at any time during flights thereof
there are some aircraft, usually for military uses, that have substantially determines the amount of torque needed to be
come to have needs for much larger amounts of electrical Supplied by the intermittent combustion engine to the electri
power either on a relative basis, the electrical power needed cal power generator. The amount of torque generated is deter
relative to the capability of the gas turbine engine available, or mined by the amount of fuel supplied to the combustion
on an absolute basis with power needs significantly exceeding 45 chambers of the intermittent combustion engine, and there is
a megawatt. Furthermore, Such demands for electrical power a corresponding amount of air that must also be Supplied to
in military aircraft often occurat relatively high altitudes and those chambers to support the desired combustion therein. At
often occur unevenly over relatively long time durations of Some altitudes and certain other flight conditions and for
use, that is, large peaks repeatedly occur in electrical power Some amounts of electrical power concurrently demanded in
demand in the course of those long use durations. 50 the aircraft, the amount of compressed air supplied by the gas
Corresponding attempts to obtain the added power from turbine engine throughan airtransport duct to the air intake of
the typical aircraft propulsive system, the gas turbine engine, the intermittent combustion engine is more or less optimal. In
that are needed to operate the concomitant much larger capac other circumstances, difficulties arise because of aircraft
ity electrical generators, either on a relative or absolute basis, operations being required at different altitudes with the atten
will subtract significantly from the thrust output of the avail 55 dant different air pressures, because of different gross
able turbine or turbines. Making up that thrust loss in these weights due to different flight missions and the consumption
circumstances by operating such available turbine engines so of fuel during flights with the attendant differing operating
as to increase the thrust output thereof causes the already powers that must be provided by the gas turbine engine, and
relatively low fuel use efficiency during flight to decrease the like.
significantly, which can severely limit the length of otherwise 60 These differing circumstances change the pressure of the
long duration uses, and also brings those engines closer to compressed air being delivered by the gas turbine engine air
becoming operationally unstable. compressor to the intermittent combustion engine, and so
One alternative to using the gas turbine engine as the sole could exceed its pressurized air containment capability or
Source of power to operate an electrical power generator is to change its torque generating capability and, correspondingly,
add in the aircraft a further intermittent combustion internal 65 the amount of electrical power generated. In these other cir
combustion engine, such as gasoline engines operating on the cumstances, the intermittent combustion engine might be
any of the Diesel, Miller, Otto or Wankel cycles. Such engines overpressured at its air intake because the compression ratio
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of the engine could increase the pressure of the already com intakes of the intermittent combustion engine at alternative
pressed air Supplied thereto to the point of some containment pressures thereby avoids severe under or over pressures with
component bursting. Alternatively, the intermittent combus respect to the optimum for operating that engine, and so
tion engine might be insufficiently pressured there to result in allows operating the aircraft at many different combinations
incomplete combustion in the combustion chambers thereof 5 of altitude, speed and gross weight with varying electrical
and so a reduced output torque. Thus, there is a desire to better power demands for each Such combination.
match the air pressure at the air intake of the intermittent FIG. 1 shows a schematic representation of a cross section
combustion engine to varying flight and electrical power side view of a portion of an aircraft with an example of such
demand conditions. a gasturbine engine and intermittent combustion engine com
10 bination, 10, in an arrangement in which most of the aircraft
BRIEF SUMMARY OF THE INVENTION structure in which they are positioned has been omitted from
this view. However, there is at least a portion of an engine
The present invention provides an engine combination for duct, 11, in that aircraft that is shown and has an air inlet, 12.
generating forces with a gas turbine engine having an air inlet facing forward in the aircraft. The configuration shown for
open to the atmosphere, an air compressor, a combustor, a 15 duct 11, with its somewhat sinuous shape, is from a stealth
turbine and an exhaust exit nozzle open to the atmosphere type military aircraft, several kinds of which are unmanned
positioned along a fluids flow path passing through all for aircraft. This duct first curves downward, coming from the
generating force with the gasturbine engine having a plurality front of the aircraft at the duct opening provided by airinlet 12
of air transfer ducts each extending from a different location to the atmosphere from which an airstream, 13, is drawn. The
therein so as to be capable to provide air in each of those air duct then curves upward to open to a gas turbine engine
transfer ducts at one end thereof at pressures differing from provided as a turbofan engine, 14, in engine duct 11 which
one another. In addition, an internal combustion engine is uses airstream 13 for combustion and for fan forced air pro
provided in the combination as an intermittent combustion pulsion purposes. This passageway curvature of duct 11 past
engine having an air intake coupled to combustion chambers air inlet 12 serves to hide the front of engine 14 from imping
therein and a rotatable output shaft for generating force also 25 ing electromagnetic radiation at various wavelengths. Outer
coupled to those combustion chambers, the plurality of air portions, 15, of duct 11 adjacent engine 14 past a splitter as a
transfer ducts each being connected at an opposite end thereof fan duct convey the fan forced air provided by engine 14 for
to the air intake to be capable of being selected to transfer air propulsion purposes into the remainder of duct 11 past engine
thereto. A plurality of control valves can be provided each at 14 toward the outlet of duct 11 to the atmosphere as will be
least provided partially in a corresponding one of the plurality 30 described below.
of air transfer ducts at least some of which control valves can This fan forced air and the combustion products resulting
be selectively directed to open more or close more to thereby from combustion in engine 14 are forced out of the remainder
selectively affect the passage of air through that air duct. A of engine duct 11 to an exit nozzle, 16, serving as the outlet of
primary electrical generator having an output conductor can duct 11. A fluid actuation system, 17, provides the force to
have a rotatable input shaft connected to the intermittent 35 partial open and close nozzle 16 during the operation of
combustion engine output shaft with the output conductor turbofan engine 14. Again, duct 11 past engine 14 first curves
being electrically energized in response to rotation of the downward, coming from that engine, and then the duct curves
input shaft. upward to open to nozzle 16. Here, too, this passageway
curvature of duct 11 past engine 14 serves to hide the rear of
BRIEF DESCRIPTION OF THE DRAWINGS 40 engine 14 from electromagnetic radiation at various wave
lengths impinging at the rear of the aircraft.
FIG. 1 is a schematic representation of a cross section side Engine 14 has an air inlet guide vane, 20, followed by a
view of a portion of an aircraft embodying the present inven high pressure fan, 21, as the fan for the turbofan engine to
tion. force air outside and past a splitter, 22, and then through duct
45 portions 15 into the rear of duct 11 and out of that duct through
DETAILED DESCRIPTION nozzle 16 to exit to the atmosphere. In addition, high pressure
fan 21 also serves as a low pressure air compressor through
A larger range of optimum, or near optimum, of pressures delivering compressed air inside splitter 22 to a high pressure
of the air supplied to the air intake of the intermittent com air compressor, 23. The compressed air from high pressure
bustion engine, during its operation over a variety of aircraft 50 compressor 23 arrives at a combustor, 24, to which fuel is also
flight conditions and aircraft electrical power electrical power delivered and burned. The combustion products form a jet of
demands, can be provided by conveying air to that intake from fluid which impinges first on a high pressure turbine, 25, and
different locations in the gas turbine engine at each of which then on a low pressure turbine, 26, to cause them to rotate
the local air pressure differs from that of the others. As an which, through appropriate mechanical linkings, leads to
example, a turbofan engine provides airstreams therethrough 55 high pressure compressor 23 and high pressure fan 21 being
with differing air pressures at different locations along the forced thereby to also rotate. The combustion products then
stream as well as different airstreams each at air pressures reach the remainder of duct 11 past engine 14 to exit through
differing from that of the other or others, and these differences nozzle 16 to the atmosphere.
occur over a large range of pressures from atmospheric at the An atmospheric air conveyance duct, 27, is connected at
engine air inlet to many times that pressure at the output 60 one end thereof through the inlet portion of duct 11 just ahead
location of the high compression air compressor. of air inlet guide vane 20 of turbofan engine 14 to receive air
The availability of these alternative airstreams, along with from that location compressed to the pressure resulting just
Some range of pressure regulation of the air drawn therefrom, from the velocity of the aircraft in flight through an atmo
allows choosing the most Suited of them for use in operating spheric air flow control valve, 27", typically controlled by a
the intermittent combustion engine with any particular com 65 system computer or controller (not shown but typically an
bination that develops of flight conditions and electrical engine control computer or an aircraft systems computer
power demands. Such selections of air Supplies to the air either eliminating the need for Such an engine control com
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puter or operating with it in a distributed control system). This 31, to provide the optimal or near optimal amount of air to
valve is used to control the flow of atmospheric air from the intake 32 to operate engine 34 in Supplying the electrical
turbofan engine inlet through duct 27 so as to be capable of power being demanded.
varying the pressure thereof to some extent. The opposite end Valves 33 in engine 34 control the air taken into combus
of duct 27 is connected to a corresponding entrance of an air 5 tion chambers, 35, bounded by an engine block, 36, providing
intake, or intake manifold, 32, leading to engine air intake the basic structure of engine 34 and by pistons, 37. Each
valves, 33, for an intermittent combustion engine, 34, repre chamber also has an exhaust valve, 38, through which com
sented in the example of FIG. 1 as a Diesel or Otto cycle bustion products are exhausted to an exhaust manifold, 39. A
engine. Control valve 27 can be closed off to prevent air rotatable crankshaft, 40, has a connecting rod, 41, rotatably
under pressure in intake manifold 32 from being forced to 10 coupling it to a corresponding one of each of pistons 37. A
flow in the opposite direction through duct 27 to the atmo rotatable camshaft, 42, is used to open and close air intake
sphere. Intermittent combustion engine 34 is shown posi valves 33 and exhaust valves 38 in a suitable sequence.
tioned forward in the aircraft of turbofan engine 14 to shift the Crankshaft 40, under the control of a system controller not
center of mass of the aircraft forward to counter some of the shown, is rotated by the force on pistons 37 transmitted
weight of engine 14 but other positions are possible to be used 15 thereto by corresponding ones of connecting rods 41 due to
if desired. repeated combustion events in the corresponding combustion
Similarly, another compressed air conveyance duct, 28, is chamber 35 which events occur in all of chambers 35 in a
connected at one end thereof into turbofan engine 14 to Suitable sequence before repeating. These events correspond
receive, rearward of splitter 22, compressed air from high ingly use the air quantities taken through Valves 33 repeatedly
pressure fan 21, as the fan for the turbofan engine that forces into, and the fuel quantities repeatedly injected into, those
engine inlet air outside and past splitter 22, which fan air is chambers for combustion. The fuel quantities are injected by
received through a compressed air flow control valve, 28', a fuel injection system not seeable in this FIGURE and, as
again typically controlled by a system computer (not shown). indicated above, the magnitudes thereofare used to select the
Here, too, this valve is used to control the flow of inlet air mechanical power output of crankshaft 40 of the intermittent
compressed by engine fan 21 taken from outer portions 15 of 25 combustion engine. The resulting combustion products are
duct 11 through duct 28 so as to be capable of varying the correspondingly repeatedly rejected from those chambers
pressure thereof to some extent. The opposite end of duct 28 through valves 38. If an Otto cycle engine is used as intermit
is connected to a corresponding entrance of air intake mani tent combustion engine 34, the combustion events are initi
fold 32. Control valve 28' can also be closed off to prevent air ated by the repeated sparkings of spark plugs not shown in
under pressure in intake manifold 32 from being forced to 30 this FIGURE in a suitable sequence across combustion cham
flow in the opposite direction therethrough. bers 35 under the control of the system controller. In addition,
A further compressed air conveyance duct, 29, is con intermittent combustion engine 34 has a cooling system not
nected at one end thereof into turbofan engine 14 through the shown for cooling the engine structure about combustion
case about high pressure compressor 23 to receive, further chambers 35.
rearward of splitter 22 but back from the output of compressor 35 The rotation of crankshaft 40 is suitably fastened to an
23, compressed air from high pressure compressor 23 at an input shaft, 43, of a primary electrical power generator, 44.
intermediate pressure less than that occurring at the output of The resulting rotation of input shaft 43 electrically energizes
that compressor but greater than that provided by fan 21, output electrical terminals, 45, of generator 44 to thereby
which intermediate pressure air is received through a com generate the desired electrical power thereat for operating
pressed airflow control valve, 29', also typically controlled by 40 aircraft devices (not or not all shown). The demand for elec
a system computer (not shown). Again, this valve is used to trical power in the aircraft is used as a basis to select the fuel
control the flow of inlet air compressed to an intermediate quantities injected in the combustion chambers of the inter
pressure by engine compressor 23 taken from case thereabout mittent combustion engine to have that engine Supply suffi
through duct 29 so as to be capable of varying the pressure cient mechanical power crankshaft 40 to sufficiently rotate
thereof to some extent. The opposite end of duct 29 is con 45 input shaft 43 of generator 44 to meet that demand.
nected to a corresponding entrance of air intake manifold 32. An exhaust duct, 46, extends from exhaust manifold 39 of
Control valve 29' can again be closed off to prevent air under intermittent combustion engine 34 to an exhaust turbine, 47.
pressure in intake manifold 32 from being forced to flow in to result in the combustion products of engine 34 impinging
the opposite direction therethrough. on the blades of that turbine to thereby cause it to rotate. A
A final and greatest capacity compressed air conveyance 50 central shaft of this exhaust turbine is coupled to an input
duct, 30, is connected at one end thereof into turbofan engine shaft of a secondary electrical power generator, 48. The
14 to receive compressed air from the output of high pressure resulting rotation of this input shaft electrically energizes
compressor 23 through a compressed air flow control valve, output electrical terminals, 49, of generator 48 to thereby
31, once again typically controlled by a system computer (not generate the further desired electrical power thereat.
shown), and used to control the flow of compressed air from 55 Another Supplemental electrical power generator is pro
high pressure compressor 23 through duct 30. The opposite vided in this example by operating an electrical starter (gen
end of duct30 is connected to a corresponding entrance of air erator), 50, with the electrical motor therein operated also as
intake manifold 32. an electrical generator after the completion of the starting
The system computer is connected to various sensors to process. Starter (generator) 50 rotates high pressure air com
determine the flight conditions occurring as well as the elec 60 pressor 23 to start turbofan engine 14 and, thereafter, with
trical power demands occurring, and controls the amount of engine 14 operating, this compressor can selectively rotate
fuel supplied to intermittent combustion engine 34 to deter the rotor in starter (generator) 50 to cause the starter motor to
mine the torque provided thereby to electrical power genera be operated as an electrical power generator.
tors to meet those power demands. This information available Starter (generator) 50 has a drive (input) shaft, 51, extend
to the system computer allows it choose which of air convey 65 ing from the rotor therein to a set of bevel gears, 52, with the
ance ducts 27, 28, 29 and 30, and the degree of opening of the bevel gear on the opposite side of this set rotatably coupled to
corresponding one of air flow control valves 27, 28, 29' and a clutch, 53. Clutch 53 allows the system computer to engage
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and disengage starter (generator) 50 as appropriate. The put conductor which is electrically energized in response to
opposite side of clutch 53 has a engagement shaft, 54, extend rotation of the input shaft thereof.
ing therefrom ending in bevel gear rotatably engaged with a 7. The combination of claim 6 further comprising a clutch
counterpart bevel gear in a portion of high pressure air com as part of the coupler which can be selectively directed to
pressor 23. engage or disengage to thereby selectively complete the cou
A further supplemental electrical power generator. 55, is pling to cause the Supplemental electrical generator input
shown in FIG. 2 for this example which has an input shaft, 56. shaft to be rotated.
extending from the rotor therein to a set of bevel gears, 57. 8. The combination of claim 1 further comprising an elec
with the bevel gear on the opposite side of this set rotatably trical starter having a rotatable operation shaft coupled
coupled to a shaft, 58, which in turn is coupled to a further set 10 through a coupler to the air compressor of the gas turbine
of bevel gears, 59. These bevel gears are coupled to an output engine such that the starter can be selectively directed to
shaft of low pressure turbine 26 through a clutch, 60. Clutch rotate a rotor in the air compressor or to have a rotor in the
60, here too, allows the system computer to engage and dis starter to be rotated by the air compressor to generate electri
engage generator 55 as appropriate. cal power.
Although the present invention has been described with 15 9. The combination of claim 8 further comprising a clutch
reference to preferred embodiments, workers skilled in the art as part of the coupler which can be selectively directed to
will recognize that changes may be made in form and detail engage or disengage to thereby selectively complete the cou
without departing from the spirit and scope of the invention. pling to allow the starter to be selectively directed to rotate a
rotor in the air compressor or to allow a rotor in the starter to
The invention claimed is: be rotated by the air compressor.
1. An engine combination for generating forces, the engine 10. The combination of claim 1 wherein one of the plurality
combination comprising: of air transfer ducts extends from the gas turbine engine so as
a gas turbine engine having an air inlet open to the atmo to receive compressed air at an output pressure from an output
sphere, an air compressor, a combustor, a turbine and an location of the air compressor, and another one of the plurality
exhaust exit nozzle open to the atmosphere all posi 25 of air transfer ducts extends from the gas turbine engine so as
tioned along a fluids flow path passing therethrough for to receive compressed air at an intermediate pressure less than
generating force, the gas turbine engine having a plural the output pressure from an intermediate location of the air
ity of air transfer ducts each extending from a different compressorbetween an input location and the output location
location therein so as to be capable to provide air in each of the air compressor.
of those air transfer ducts at one end thereofat pressures 30 11. The combination of claim 1 wherein the engine com
differing from one another, and bination is in an aircraft propelled by the gas turbine engine
an internal combustion engine provided as an intermittent that is a turbofan engine having an enginefan located between
combustion engine having an air intake coupled to com the air inlet and the air compressor to force air both into the sir
bustion chambers therein and a rotatable output shaft compressor and a fan duct outside of the air compressor, and
also coupled to those combustion chambers for generat 35 wherein one of the plurality of air transfer ducts extends from
ing force, the plurality of air transfer ducts each being the gas turbine engine so as to receive compressed air at an
connected at an opposite end thereof to the air intake to output pressure from an output location of the air compressor,
be capable of being selected to transfer air thereto. and another one of the plurality of air transfer ducts extends
2. The combination of claim 1 further comprising a plural from the gas turbine engine so as to receive compressed air at
ity of control valves each at least provided partially in a 40 a fan duct pressure less than the output pressure from a fan
corresponding one of the plurality of air transfer ducts at least duct location outside of the air compressor.
some of which control valves can be selectively directed to 12. The combination of claim 1 wherein one of the plurality
open more or close more to thereby selectively affect the of air transfer ducts extends from the gas turbine engine so as
passage of air through that air duct. to receive compressed air at an output pressure from an output
3. The combination of claim 1 wherein at some of the a 45 location of the air compressor, and another one of the plurality
plurality of control valves can be closed to prevent passages of air transfer ducts extends from the air inlet of the gas
of air through the air transfer duct in which it is provided. turbine engine so as to receive air at an inlet pressure less than
4. The combination of claim 1 further comprising a pri the output pressure from an airinlet location of the gasturbine
mary electrical generator having a rotatable input shaft engine.
mechanically coupled through a coupler to the intermittent 50 13. The combination of claim 1 wherein the intermittent
combustion engine output shaft and having an output conduc combustion engine is positioned at least in part forward of the
tor, the output conductor being electrically energized in gas turbine engine in an aircraft propelled by the gas turbine
response to rotation of the input shaft. engine.
5. The combination of claim 1 wherein the intermittent 14. The combination of claim 1 wherein the engine com
combustion engine has an exhaust outlet coupled to the com 55 bination is in an aircraft propelled by the gas turbine engine
bustion chambers therein and further comprises an intermit that is a turbofan engine.
tent combustion engine exhaust turbine positioned at the 15. A method of generating force and electrical power
exhaust outlet and a secondary electrical generator having a using an engine combination of a gas turbine engine having
rotatable input shaft mechanically coupled through a coupler an air inlet open to the atmosphere, an air compressor, a
to an intermittent combustion engine exhaust turbine output 60 combustor, a turbine and an exhaust exit nozzle open to the
shaft, the secondary electrical generator having an output atmosphere all positioned along a fluids flow path passing
conductor which is electrically energized in response to rota therethrough and of an internal combustion engine provided
tion of the input shaft thereof. as an intermittent combustion engine having an air intake
6. The combination of claim 1 further comprising a Supple coupled to combustion chambers therein, a fuel system
mental electrical generator having a rotatable input shaft 65 coupled to those combustion chambers and a rotatable output
coupled through a coupler to the turbine of the gas turbine shaft also coupled to those combustion chambers, there being
engine, the Supplemental electrical generator having an out a plurality of air transfer ducts each extending from a different
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location in the gas turbine engine so as to be capable to air in each of those air transfer ducts at one end thereof
provide air in each of those air transfer ducts at one end at pressures differing from one another;
thereof at pressures differing from one another to the air an internal combustion engine provided as an intermittent
intake, the method comprising: combustion engine in the aircraft having an air intake
operating the gas turbine engine to establish a combustion 5 coupled to combustion chambers therein, a rotatable
products flow out the exhaust exit nozzle: output shaft also coupled to those combustion chambers
for generating force, and a fuel system for providing fuel
Selecting an air transfer duct for distributing air from its to those combustion chambers, the plurality of air trans
location in the gas turbine engine, and fer ducts each being connected to the air intake to trans
distributing air through the selected air transfer duct to the 10 fer air thereto, and
air intake of the intermittent combustion engine. a primary electrical generator in the aircraft having a rotat
16. The method of claim 15 further comprising a plurality able input shaft mechanically coupled through a coupler
of control valves each between the location of a correspond to the intermittent combustion engine output shaft and
ing one of the air transfer ducts in the gas turbine engine and having an output conductor with the output conductor
the air intake which can be selectively directed to open more being electrically energized in response to rotation of the
15 input shaft.
or close more to thereby selectively affect the passage of air
through that air duct. 19. The combination of claim 18 further comprising a
17. The method of claim 15 further comprising an electri plurality of control valves each between the location of a
cal power generator having an input shaft coupled to the corresponding one of the air transfer ducts in the turbofan
output shaft of the intermittent combustion engine with the engine and the air intake which can be selectively directed to
electrical power generator having output conductors which open more or close more to thereby selectively affect the
are electrically energized by rotating the input shaft, and passage of air through that air duct.
20. The combination of claim 18 wherein the aircraft is an
selecting quantities of fuel to be injected into the combustion unmanned stealth type aircraft.
chambers of the intermittent combustion engine based at least 21. The combination of claim 18 wherein the intermittent
in part on the demand for electrical power at the output 25 combustion engine is positioned at least in part forward of the
conductors of the electrical power generator. turbofan engine in an aircraft propelled by the turbofan
18. A power generation system for propelling, and gener engine.
ating electrical power in, an aircraft, the system comprising: 22. The combination of claim 18 further comprising the
a turbofan engine in an engine compartment in the aircraft aircraft having selectively operated electrical power con
with an air inlet in the aircraft open to the atmosphere 30 Sumption devices therein electrically connected or connect
and leading to an air compressor in the turbofan engine able to the output conductor of the primary electrical genera
followed by a combustor, the gas turbine engine having tor to receive electrical power therefrom.
a plurality of air transfer ducts each extending from a
different location therein so as to be capable to provide k k k k k