Global Needs for Jet-Engine-Steered (JES) Strike Drones vs. Lack of Updated Textbooks to Design 6^th Generation UCLASS Due to UCAV Failure

Mission, Budget, Base, Armaments, Engine Type Iterations

Early iterations in conceptual design of JES-Strike Drones involve:

1. MISSION: Follow what potential rivals do [E.g., Refs 22, 23]. Determine variable and invariable technology limits associated with updated JES-Strike Drones vs. the spectrum of knowledge mastered by the local team regarding said technology limitations to be encountered during global, coalitional or individual fights against terror, as well as during geopolitical and strategic issues vs. tactical operation-deterrence regarding verifiable information on potential targets, like high or low contested areas; type, location, protection and number of targets; refueling issues avoidable or not (Cf. BASE below); mission-area-intelligence on, say, SA missiles, rival drones, manned air vehicles, cruise missiles, subs vs. mix of ready friendly means; confidentiality restrains, educational and training issues, etc.

2. BUDGET: Range and RFP-funding-spread from conceptual design to initial designs followed by models-prototype laboratory-based tests; then followed by early prototype-flight-tests, then followed by the more traditional evaluations, production, training, fielding, operation, maintenance, repairs, grows, modular plans, etc.

3. BASE: Short range launches by or from a friendly area ground (Cf. Mission), air or sea launching bases vs. long range, carrier launched into a remote, potentially hostile areas; one or two circles vs. endurance time, size, refueling, etc.

4. ARMAMENT: Verifiable effects on various target types, other potential threats; geographical structure-location; spread-density-type-numbers of targets; selected drones’ accessibility and penetrability; minimal stealth degree required; time-over-target needed; issues regarding strategic and legal subjects vs. associated volume-weight, safety, storage, maintenance, etc.

5. ENGINE TYPE: Budget and maturation-time-issues (see below) are expected to curb the development of new special engines for such applications, except modular adaptation of JES and JES-training needs. A specific example of sub-iteration: Long mission endurance may dictate larger-diameter turbofans, with less required fuel tanks volume-weight, while low-by-pass, smaller-diameter jet engines may dictate larger fuel tanks capacity; Other specific issues may include design for best HTM-JES capabilities [Figure 2].

6. OTHER FACTORS: The design and operation of JES-STRIKE-DRONES and/or future UCLASS fleets [1, 2], need involve an optimal mix of (I) extant, subsonic, propeller-driven drones, (II) huge potential fleets of popular, lowest-cost, “sporty-type”, subsonic, piston-engine-fan-cold-jet-based, JES-drones now available anywhere [22, 23], (III) faster, more expensive, stealth, JES-based, post-stall, super-agile, strike drones, capable of performing Helicopter Type Maneuvers [Figure 2]. In sum, to review the entire spectrum of such new challenges, would certainly require an additional editorial and the writing, or co-writing of reliable, updated, design textbook.

The No-Option Rules

Within the JES-Stealth revolution, the jet engine is not arrested to provide only brute force forward, because it is becoming at least co-prime flight controller [3–21].

“Cow and Horse Cannot Work Together in JES Systems”, namely, during rotational-rates via fluidics or mechanical JES systems.

JES masters flight control in post-stall situations.

JES-based-drone pilots should master jet-engine dynamics, including compressor maps and IFPC (Integrated Flight Propulsion Control, Figure 4.).

Airframe, flight control-computer and armaments R&D and maturity in isolation from JES inlets, engine and exhausts, is futile.

Time to certify a new, complete, operational propulsion JES-system, is much longer than to certify new wings, airframe, landing gear, electronics, computers, hydraulics, etc.

JES-based SACOM

Conceptual design, evaluation and small prototype flight testing of a new JES system via verifiable, Standard Agility Comparison Maneuvers [“SACOM”] for each selected JES-Stealth system is a must [4].

Helicopter and other JES-based maneuvers, recovery from adverse whether cases, missing the runway, airframe-hydraulics failures, require similar verifiable SACOM [4].

Jet-Engine Exhaust Nozzle-Design-Options

1. Low-cost options for drones or experimental evaluations, involve 3 or 4 post-nozzle, external jet deflectors of the X-31 or F-18 HARV types.

2. Divergent nozzle JES-deflections covered by external stealth aerodynamic surfaces of the F-22 type are good options, unless fluidic systems are the optimal solutions.

3. Extra added JES-ring and actuators linked to IFPC (Figure 4), as first adopted by non-stealth F-15 ACTIVE and F-16 MATV/VISTA are good.

4. JES-rotation of the entire, non-stealthy, supersonic, variable exhaust nozzle, as adopted in Russian non-stealthy designs, like the SU-30-MKI is good.

5. Non-mechanical, low-weight Fluidic JES as discussed above, is effected by extracting air from the engine compressor to inject it in the diverging section of the engine exhaust nozzle, an effective method especially useful for JES-based cruise missiles and drones.

6. Sea JES technologies involve water-jet-steering with fixed-water-jet-nozzle-geometry that propels-steers super-agile sea vehicles, manned and unmanned, ranging from small sporty wave-riders to unmanned attack boats, super-agile patrol and missile boats, up in size to various new Littoral Combat Ships [LCS].

7. Subsonic, low-thrust-to-weight ratio passengers or cargo jets, turboprops and helicopters, may incorporate patented, stowed-away/emergency-deployed JES-systems installed inside the fixed-geometry, subsonic, jet-engine nozzles, or inside the subsonic engine nacelles [7–9].

8. Front/back/side-installed series of small emergency water-jets automatically operated to stop dangerous pitch-up/rolling/skidding of speed, patrol and missile water-jet-boats, or similarly operated, safe-azid-type-gaseous jets automatically operated to stop dangerous pitch-up/rolling/skidding of racing or regular cars, SUVs, buses and trucks [video in Facebook].

9. The complex, sluggish and expensive JES-systems installed on the single engine, reduced super-agility, reduced stealth F-35.

10. Experimental, X-49-type, fan-rudder system used by lake-water-boats, and adopted to a new prototype helicopter.

11. There is no need for canards in advanced piloted or unpiloted, JES-based, effective, stealth air vehicles. Canards, as we have claimed since 1986, reduce post stall performance and introduce adverse stealth issues. This No-Canards Rule took about 25 years for the Russian and Chinese designers to follow. The EU has not yet followed.