Designed Flexibility

The business of the fighter-bomber is weapons delivery, and the F-15E is equally as capable in both the air-to-air and air-to-ground roles. This provides enormous flexibility to military planners who must take into account the unpredictable nature of warfare. While the primary role of the F-15E is as a strike aircraft, it could theoretically be used to defend an airspace as well. The ability to carry a mixed load of air-to-air and air-to-surface weapons also means that the aircraft has the capacity to defend itself while performing the strike role. The F-15E is capable of fielding nearly every weapon system in the USAF's inventory, including a wide range of precision-strike ordnance. In addition to the sheer variety of weapons that the F-15E is capable of delivering, the design features of the aircraft allow it to carry aloft an impressive amount of ordnance. The F-15E owes this to both the structural enhancements to its airframe, and the Conformal Fuel Tanks that grace its lines.

Conformal Fuel Tanks

One of the features that makes the F-15E a most impressive fighter-bomber is the pair of Conformal Fuel Tanks (CFTs) that run along either side of the fuselage. In addition to providing a considerable fuel supply to the aircraft without the extensive drag penalty of external tanks, the CFTs provide additional hardpoints from which ordnance can be mounted.

Mounting ordnance to the CFTs reduce drag forces typically imposed by the Multiple Ejector Racks (MERs) common to other military aircraft. MERs cluster bombs close beside each other in the airstream, resulting in each bomb interfering with the accelerated airflow around each of the other bombs. This causes increased levels of interference drag between the bombs on each MER. This in turn affects both aircraft performance as well as bombing accuracy as these drag forces create excessive pitching and yawing motions on the bombs upon initial release.

The F-15E's CFTs mount ordnance conformally in order to reduce drag. Conformal carriage refers to positioning the hardpoints so that ordnance follows the contour of the structure that they are being mounted to. In the case of the F-15E, bombs are laid along each CFT in two rows. In each row, the forward hardpoint positions the bomb slightly nose-up, the centre hardpoint mounts the bomb level to the aircraft, while the aft hardpoint positions the bomb slightly nose-down. This results in a cleaner airflow around the bombs which in turn, reduces the interference drag common among MERs. As a result, airflow around the aircraft is cleaner as well. This translates into increased performance, speed, and range for the aircraft as compared to a similar bomb load utilising MERs.

Each CFT features a lower row made up of a continuous ordnance pylon running fore-to-aft, and an upper row made up of three stub pylons. The lower row can be configured in order to mount two air-to-air missiles, three small bombs such as the Mk-82, two large bombs such as the Mk-84, or two bombs with guidance-packages. The upper row typically features one small bomb per pylon for a total of three bombs, or a total of two small bombs equipped with guidance-packages. No air-to-air missiles can be mounted along this upper row.

Additional Hardpoints

In addition to the CFTs, the F-15E features three additional hardpoints, one on each wing and a single hardpoint along the aircraft centreline. These hardpoints are "wet", each capable of accommodating a 600 US gal. fuel tank which can be discarded. MERs can be mounted on these hardpoints in order to increase the warload of the F-15E if necessary. Extremely heavy ordnance or air-to-surface missiles are mounted on the wing-stations due to the strength and clearance of this hardpoint.

Air-to-Air Weapons

Each CFT has the capacity for carrying a pair of air-to-air missiles on its lower rack, either AIM-7 Sparrows or AIM-120 AMRAAMs. From these stations, missiles are "cold-launched", a process that involves ejecting the missile down and away from the CFT before its rocket motor engages. For the sake of flexibility, air-to-air missiles can be mounted on one CFT while air-to-ground ordnance is mounted on the other. This option was seen occasionally during the Gulf War.

Mounted along either side of the wing pylons are LAU-114 launch rails for AIM-9 Sidewinders, AIM-120 AMRAAMs, or any combination of the two. This allows the F-15E to field at least four air-to-air missiles, even while the CFTs are carrying air-to-ground ordnance. This has obvious self-protection benefits for the aircraft while performing the strike role.

F-15E Ordnance Loads

			X		A	B		C		D	E		Y
AIM-7 Sparrow						2				2
AIM-9 Sidewinder			2										2
AIM-120 AMRAAM			2			2				2			2
AGM-65 Maverick					3						3
AGM-130 (2000 lbs)					1						1
GBU-10 -24 (2000 lbs)					1	2		1		2	1
GBU-12 (500 lbs)					2	4		2		4	2
GBU-15 (2000 lbs)					1						1
GBU-28 (4700 lbs)					1						1
Mk-82 (500 lbs)					6	6		6		6	6
Mk-84 (2000 lbs)					1	2		1		2	1
BLU-109					1	2		1		2	1
Cluster Munitions					6	6		6		6	6
600 US gal tank					1			1			1
SUU-20 Practice Carrier					1			1			1

M61A1 Vulcan Cannon

As with all F-15s, the fixed weapon of the F-15E is the 20mm General Electric M61A1 Vulcan cannon. This weapon features six rotating barrels which allows for a firing-rate of approximately 6 000 rounds per minute, while at the same time reducing erosion of the barrels, resulting in extended service-life. The rotary action for the F-15's M61A1 is supplied by hydraulic/electrical power.

The barrels and drive mechanism of the cannon are located in the starboard wing root of the F-15E while the 512-round ammunition drum is located along the aircraft's centreline between the forward and centre-fuselage fuel tanks. The F-15E's ammunition drum carries a total of 512 rounds as compared to the A through D models of the F-15 which carry a maximum of 940 rounds. A linkless feed chute runs between gun and ammunition drum, supplying the cannon with the ammunition and transporting the spent casings back to the drum. The M61A1 uses the M50 series of 20mm ammunition._