The US Air Force's B-1 bomber, also known as the B-1B Lancer, is a long-range, multi-role bomber aircraft designed to reduce its radar signature, making it more difficult to detect by enemy air defences.
The B-1's shape, materials and systems contribute to its low observability.
The aircraft's distinctive shape is designed to deflect radar waves away from the aircraft and reduce its radar cross-section (RCS). The bomber's surfaces are also coated with a special radar-absorbing material that helps to further reduce its RCS.
The B-1 also employs a number of advanced systems to reduce its radar signature.
The aircraft's engines, for example, are equipped with a "serpentine" exhaust system that helps to reduce their heat signature and make them less visible to infrared sensors.
The aircraft is equipped with the Synthetic Aperture Radar (SAR) and the Multi-Mode Radar (MMR), which allow it to detect and track targets on the ground, even in adverse weather conditions. The B-1 also has a targeting pod that can be used to identify and track targets on the ground or in the air.
Other features that help to reduce the B-1's visibility include its low observable cockpit, which is designed to reduce the reflection of radar waves, and its use of advanced sensors and avionics that allow it to detect and avoid enemy threats before the aircraft is detected.
The multi-mission B-1 is the backbone of the US Air Force's long-range bomber force. It carries the largest conventional payload of both guided and unguided weapons in the Air Force's inventory.
The B-1 has a maximum speed of Mach 1.25 (957 mph), and a range of over 9,656km. It has a maximum takeoff weight of 477,000 pounds (216,363kg) and can carry up to 75,000 pounds (34,000kg) of weapons and fuel.
This means that after the aircraft carries out a surprise attack against enemy targets deep into hostile territory, it is able to outrun enemy fighter jets and escape unharmed.
The B-1 holds almost 50 world records for speed, payload, range and time of climb in its class.
It can rapidly deliver massive quantities of precision and non-precision weapons against any adversary, anywhere in the world, at any time.
The aircraft's advanced sensors and targeting systems allow it to gather intelligence on enemy forces and provide real-time situational awareness to ground forces.
The B-1 bomber's ability to fly at high speeds and altitudes also makes it difficult for enemy defences to detect and intercept, allowing it to conduct reconnaissance missions with relative impunity.
Payload capabilities
The B-1's low observability is especially important when considering the aircraft's payload capabilities.
US strategic bombers are able to carry a variety of nuclear and non-nuclear precision guided munitions, such as the AGM-86 Air Launched Cruise Missile (ALCM), AGM-158 Joint Air-to-Surface Standoff Missile (JASSM) and the Joint Direct Attack Munition (JDAM).
The ALCM is a cruise missile that aims to dilute an enemy's forces and complicate defence of its territory. An enemy force would have to counterattack each of the missiles, making defence against them costly and complicated, according to the US Air Force.
"The enemy's defences are further hampered by the missiles' smallness and low-altitude flight capability, which make them difficult to detect on radar," it said.
The JASSM is a low observable standoff air-launched cruise missile with a range of 370km, while the JASSM Extended Range (JASSM-ER) has a range of approximately 1,000km.
Equipped with 432kg warheads, the JASSM and JASSM-ER feature identical, low observable airframes designed to evade enemy air defences.
The missiles are also equipped with an inertial navigation system/global positioning system (INS/GPS) unit developed for the JDAM and Joint Standoff Weapon bombs, an infrared seeker for terminal guidance, and a variety of special packages like electronic jamming.
The JASSM-ER when equipped with a weapon data link can correct course after launch, enabling it to hit moving targets on land or at sea.
Deliveries to the US Air Force of another variant of the missile, the JASSM-XR (Extreme Range) with a range of approximately 1,800km, are expected to begin in January 2024.
The JDAM is a guidance tail kit that converts existing unguided free-fall bombs into accurate, adverse weather "smart" munitions. JDAM enables multiple weapons to be directed against single or multiple targets on a single pass.
Global mission support
The US Air Force is said to have 45 B-1 bombers in its fleet, which are based at Dyess Air Force Base in Texas and Ellsworth Air Force Base in South Dakota.
The fleet has been used in a number of military campaigns over the years, including the Gulf War, the War in Afghanistan and the Iraq War.
The aircraft has also been used to provide support for humanitarian missions, such as relief efforts in Haiti and Somalia.
The B-1s represent about a third of the US Air Force's bomber fleet -- now made up of B-1 Lancers, B-2 Spirits and B-52 Stratofortresses.
This fleet will look very different in the coming years following the unveiling of the new B-21 Raider, which is expected to start service in 2027.
The US Air Force regularly carries out Bomber Task Force (BTF) missions with partner nations to reinforce partnership and joint regional security commitment.
A range of forward operating bases around the world enables US strategic bombers to strike at targets in the Middle East and Africa at a moment's notice if and when conflict erupts.
The latest BTF mission was held March 12 in the US Central Command (CENTCOM) area of responsibility, which includes the Middle East and West/Central Asia.
"The coalition conducts these integration events over partner nation airspace to expand our combined global reach and military power projection capabilities," said Ninth Air Force deputy commander Maj. Gen. Mark Slocum.
In February, the US Air Force participated in a routine BTF mission with Estonia.
The two nations are NATO allies and work in close co-ordination to safeguard the Baltic States and Europe's eastern flank.
Much focus has recently been placed on the Arabian Sea -- the waterway that all Iranian ships must pass to reach world ports, and a key link in China's "string of pearls".
Iran has long threatened to close the Strait of Hormuz, which links the Arabian Gulf with the Gulf of Oman and the Arabian Sea, and to attack maritime vessels in the event of war.
Meanwhile, China's massive infrastructure drive to connect its mainland to the Horn of Africa via a network of military and commercial facilities in recent years has raised concerns.