Download - On stealth aircraft
On stealth fighters
Value of radar stealth● stealth proponents see stealth as game-
changing technology, but history shows that:● game-changing technologies usually cheap and
simple compared to most other technologies of the era
● basic facts of warfare are mutable to the point of qualitative superiority being more advantageous than quantitative superiority only over very long time period
● forces are always in danger of being attacked in "safe" areas
What this means in war● stealth aircraft are in danger of being
overwhelmed by large numbers of small, cheap fighters equipped with RWR and/or IRST
● even if enemy does not use IRST and cannot detect stealth aircraft except visually, and stealth aircraft do not engage opponent in visual range themselves, air bases remain vulnerable to attack; once stealth aircraft are tied in defending the bases, advantage of radar stealth is all but gone
● all stealth aircraft to date require large concrete runways: cannot land if these are destroyed
What this means in war● "base camping" / "base tendering": numerically
superior opponent can use numbers to prevent stealth aircraft from taking off from or landing on their easily-visible runways
● air base vandalism: destruction of runway by cruise missiles or other means prevents operation until runway is repaired; concrete runways take long time to repair, and are easily found
Importance of numbers● ability to cover more area● slows down or breaks opponent's OODA loop
by causing information saturation● higher resillience to unavoidable attrition
● increase in total number of combatants in the air leads exchange ratio towards parity irrespective of individual unit quality
● numerical advantage increases possibility of getting first shot
Importance of numbers● Lanchester square ratio:
● per-unit quality of outnumbered force must be square of force ratio
● but per-unit quality usually increases linearly with cost - twice as expensive aircraft at best twice as effective
● higher complexity results in lower sortie rate per aircraft
● rely on low-cost technologies that provide disproportionate increase in effectiveness to compensate
Revolutionary, but too few
Situational Awareness game● passive vs active sensors● detection
● visual● electronic
– active (radar)– passive (RWR)
● infrared
Situational Awareness game● goal: detect enemy first without being detected
● can only be achieved by passive sensors● reduced signatures
– infrared– visual– electronic
● no or minimum emissions (radar, IFF, communications, uplinks)● also applies while on the ground
– underground air bases– if air base is in open, use dirt air strips and minimum
infrastructure - requires resillient, maintenance-friendly aircraft
● Typhoon equipped with advanced RWR● F-22 is likely to encounter opponents with
similar technology in any war it might be used in
Game-changers?● IRST
● QWIP IRST allows for completely passive detection of subsonic passive opponent at distances of over 50 nm (90 km) head-on, 90 nm (145 km) tail-on
● RWR● detects enemy radar emissions
● passive radar● jammers
● radar● IR
Situational Awareness: conclusion● stealth fighters no longer have SA advantage● smaller fighters will be detected later,
irrespective of any expensive radar LO measures applied to larger fighters
● reliance on passive sensors and visual detection
BVR combat● stealth fighters based around idea of radar-based BVR combat● requires active emissions - surrenders SA advantage to the
opponent● allows opponent to identify and engage it from BVR
completely passively● gives opponent starting advantage in OODA loop● radar can be jammed
● high complexity● high cost● low reliability => per-missile Pk ≤0,08 between capable
opponents● only effective against far less capable and less numerous
opponents● 10 - 15 seconds electronic acquisition for cooperative target
WVR combat● requirements
● large force size– low cost aircraft– high sortie rate
● situational awareness– cockpit visibility– sensor coverage
● high maneuverability– fast transients– high turn rate
● low wing loading– quick acceleration and climb
● low drag● high thrust-to-weight ratio
WVR combat● requirements
● good combat persistence– low drag– high fuel fraction
● reliable kills– weapon requirements
● high Pk● adequate ammo● minimum time-on-target required for the aircraft● minimum vulnerability to countermeasures (simple targeting
process)– IR jammers make IR missiles more vulnerable to
countermeasures → return of gun-only dogfights??
Force size: F-22 Raptor vs JAS-39 Gripen
● Flyaway cost: 250 million USD vs 40 million USD
● Maintenance cost per hour of flight: 61 000 USD vs 4 700 USD
● Maintenance downtime per hour of flight: 45 hours vs 10 hours
● For 1 billion USD:● 4 F-22s flying 15 1-hour sorties per week● 25 JAS-39s flying 382 1-hour sorties per week
F-22 Raptor vs JAS-39 Gripen
Flyaway cost Maintenance cost Aircraft for 1 billion USD Sorties per week
F-22JAS-39
Force size: F-22A vs F-15C● Flyaway cost: 250 million USD vs 108,2 million
USD● Maintenance cost per hour of flight: 61 000
USD vs 30 000 USD● Sortie rate: 0,5 vs 1,0
F-22A vs F-15C
Flyaway cost Maintenance cost per hour of flight Aircraft for 1 billion USD Sorties per week
F-22AF-15C
Ground threats● radar stealth dependant on size of shaping
features relative to wavelength● F-22 and F-35 typical fighters in size and
configuration; same for J-20, J-31 and PAK FA● Result: easily detected by VHF, HF and passive
radars
VHF radar - Nebo SVU
● Written by:● Picard578
– defenseissues.wordpress.com