The Javelin is a much talked about “sports jet” and military trainer and great things are claimed of it. It is manufactured by ATG in Albuquerque
with assistance from IAI of Israel. Soon after September 11th it was marketed as a possible “homeland defense fighter”.
The Homeland defense fighter concept
The single overriding concern is expense: the current use of USAF/NATO aircraft to defend America’s skies from hijacked airlines (and the like) is
costing around $1.2billion per year(!). That is despite the relative scaling down since the operational highpoint in the months immediately following
the Twin Towers atrocity. To put the level of commitment into perspective, the operation monitors more than 80,000 domestic departures and landings
every day, and supervises around 7,000 incoming “tracks”. Every time one of these aircrafts acts suspiciously, a fighter is scrambled or diverted
to intercept. Although this happens only 0.001% of the time, that corresponds to around 24 ‘live’ intercepts per month. The operation typically
ties down 35 fighter aircraft (mostly Air National Guard F-16s), 8 tankers and 3 E-3 AWACS.
The commitment is also robbing the Air National Guard units of routine training and has created pilot recruitment and retention problems because of
The much proffered solution is to equip much cheaper lightweight jets, such as the Javelin, with the means to shoot down airliners and so replace the
front line types in this role. This has perceived operating efficiencies.
The practicalities of using the Javelin
The Javelin is certainly cheaper than a ‘proper’ fighter at $5million for the basic military trainer model ($2.5 million for the baseline civilian
model). I estimate that as a homeland defense fighter it would have a price tag of around $8 million.
Artist’s impression of Javelin Homeland Defense Fighter, commissioned by author:
On paper the military trainer model has a cruising speed of Mach 0.85, a maximum speed of around Mach 0.95 (estimate by author
) and a climb
rate of 8,000ft/min with half-fuel (10,000ft/min with minimal fuel). It has a thrust to weight ratio of 0.53:1 (i.e. only half as much thrust as it is
However, we have to consider what modifications would have to be made to accommodate a basic intercept mission and how they’d affect performance:
Older versions of the Sidewinder (AIM-9L) are the obvious candidates being relatively light and all-aspect. Singers would be far lighter but are less
suited. In order to save weight the aircraft could be configured to carrying just one missile, but that would seriously compromise kill-rate.
Sidewinders have a launch weight of around 180lb and related modifications (launch rails, systems) would add around a further 300lbs, totally around
660lb. The missiles would have to be carried externally adding significant drag.
This would be the back-up for the missiles. Machine guns are not powerful enough, and the Vulcan 20mm gatling gn standard on most USAF combat aircraft
would be too big and heavy. A single 20mm canon with 150 rounds seems more sensible; estimate weight about 1000lb. The cannon could be mounted in a
belly pack with the ammo situated where the rear seat of the existing models is.
This poses a real problem; incorporating a radar set into the nose of the aircraft would require a major redesign and shift the centre of gravity
forwards. A cheaper and probably less troublesome option would be to mount the radar in a pod under the fuselage, but it would be heavy and incur a
Thinking around for possible alternatives to mounting a radar, two options spring to mind; having a “virtual radar” which repeats third-party
radar information into the cockpit (from AWACS and ground units), or using much lighter IR sensors for intercept. Neither solution would be as useful
as mounting a radar.
Overall we are looking at around 3000lb extra weight, and that’s on the optimistic assumption that the airframe wouldn’t need to be re-stressed.
And add to that a lot of extra drag and trim problems. The slated performance would degrade significantly; my revised estimates are an intercept speed
of around Mach 0.75, a thrust to weight ratio of just 0.38:1 (!) and a rate of climb in the region of 5000ft/min.
Could the modified Javelin practicably intercept an airliner?
The first and most obvious problem is that most airliners are capable of similar if not greater speeds than the modified Javelin. If the Javelin were
required to intercept the target within 15 minutes of the it being considered a threat, it would have to start its intercept run no more than 140nm
(163miles) from the intercept point (see below
). This distance would be significantly reduced if the Javelin were scrambled from a ground
The limited fuel of the Javelin would also be a major problem and air-air refueling would be too heavy a modification to make. With only 280 gallons
of fuel, its ability to perform a CAP (combat air patrol, i.e. loiter on station), would be unviable. The combination of inadequate time-on-station
performance, and poor speed would mean that far more Javelins, stationed at many more bases, would be needed to effectively cover the US.
What would have to be done to make it capable of the task
To be up to the task, a major redesign to bring it closer to proper front line fighters would be needed. By the time you’ve added an nose mounted
radar, air-air refueling, additional fuel, much more powerful engines and re-stressed the airframe, you’d end up with an all new aircraft type with
none of the cost benefits attributed to the baseline Javelin. And it would probably still be worse at it than existing frontline types.
There are a couple of other problems which haven’t been addressed. The first is that the whole Operation Noble Eagle and homeland defense fighter
concept is geared towards intercepting airliners. But the threat may be from other air vehicle types, such as cruise missiles or a ‘disaffection’
military pilot in a warplane taking off from within the US. If the Javelin would have trouble catching an airliner, it is far beneath the task of
intercepting a cruise missile.
The other concern is what I call “mission slip”. The best analogy is the British and their invention of battlecruisers. Battlecruisers where for
many years the bee’s knees of naval warfare, combining the firepower of battleships with the speed of cruisers. At the outset they were intended to
be used for scouting and for hit and run tactics, but with such mighty firepower, their commanders could not resist the temptation to employ them like
battleships even though they were woefully under-armored. Many were thus sunk engaging targets they weren’t designed to engage (such as
The parallel is that any budget homeland defense fighter, which in reality isn’t up to the role of frontline combat aircraft, would none the less
become a substitute for a ‘real fighter’, and be employed in unsuitable roles. And if the USAF purchases this genre of aircraft, it will tomorrow
be told it has more fighters than it needs by penny pinching politicians who will not adequately appreciate the difference between a front line combat
aircraft and a jazzed up sports jet masquerading as a fighter.