With 261 passengers on board, a Boeing 757 takes off from the Moi International Airport in Mombasa, Kenya, on its way to Israel. But right as the plane takes off, two missiles whiz by the left wing of the aircraft. They miss, and the passengers only experience a loud noise. But in an Israeli-owned hotel in the same city, people are not so lucky. 15 die, and a Lebanese terrorist group called the Army of Palestine takes responsibility for both attacks (1).

The missiles fired at the commercial jet that day originated from man-portable air-defense systems (MANPADS). Originally developed during the Cold War as convenient anti-aircraft weapons, MANPADS have since seeped through black markets worldwide (2). Today, several thousand MANPADS do not belong to a national government (2); an estimated 24 terrorist groups have MANPADS, each equipped with an infrared sensor that guides the missile to the hot engine of a target aircraft (3). Since 1973, there have been fifty recorded MANPADS attacks on civilian aircraft, bringing the death toll to 920 (4).

Of the two attacks in Mombasa in 2002, the bombing did prove to be the more destructive. But had the MANPADS been angled slightly differently upon launch, and the infrared tracking system a little more accurate, the death toll would have been 276 instead of 15—almost 19 times greater. Furthermore, at the 2003 Asia-Pacific Economic Cooperation forum, Secretary of State Colin Powell declared that “no threat is more serious to aviation” than MANPADS (5).

Use in Terrorism

The destructive potential of MANPADS has proven itself in a number of high-profile attacks, including the one that began the Rwandan genocide.

In 1994, tensions were high as two warring ethnic groups in Rwanda, the Hutus and the Tutsis, struggled to implement agreed-upon peace accords. The presidents of Rwanda and Burundi flew to Rwanda from a regional summit in Tanzania, but as their plane prepared to land, a missile was launched using MANPADS nearby (2). Junvénal Habyarimana, the assassinated Rwandan president, was a dictatorial leader that promoted national hatred against the Tutsis throughout his regime. Habyarimana’s death was seen as an attack from the opposition and reignited a civil war. The subsequent genocide that would result in 800,000 deaths over the course of 100 days. It is still unknown who was responsible for the attacks.

How They Work

MANPADS operate by using one of two main guidance mechanisms: passive homing and command guidance. Both systems make MANPADS usable by a single operator, making it a convenient tool for the military and insurgents.

In passive homing, the MANPADS missiles take advantage of the infrared rays emitted by the aircraft’s engine (4). The warheads are equipped with sensor units that detect this radiation and internal programming that controls the missiles to follow these rays on their own. These “fire and forget” missiles require no operator input after launch and are the most widely used systems. However, their automated function also makes them the most susceptible to decoys. The Russian Igla, pictured in Fig 2., is the most well-known of MANPADS that employed this system, and its design has been frequently copied in missiles developed by militaries.

A passive homing MANPADS consists of a launch tube, a gripstock, and a battery coolant unit (4). Each warhead comes fitted into its own sealed launch tube, as the launch tube is typically disposed of after firing. The launch tube comes with the sight assembly and sockets into which the gripstock fits. The launch tube and warhead are together referred to as the “missile round.”

The gripstock, which is the triggering unit, is detachable and fits into the launch tube (4). The battery coolant unit (BCU) is a disposable component inserted into either the gripstock or the launch tube, depending on the model. A thermal battery in the BCU provides energy to the system for 30 to 90 seconds after activation as the missile prepares to launch, and a pressurized gas tank cools the warhead’s seeker—perhaps the most critical component of the entire system. A fully assembled MANPADS, complete with loaded launch tube, gripstock, and BCU, is referred to as a weapon round.

Unlike passive homing missiles, command guidance missiles depend on their operator to reach their target (4). Although their overall mechanisms are very similar to that of passive homing weapon rounds, the missiles are lighter and cheaper, as their function is less dependent on systems built into the missiles themselves. Instead, an operator uses a bulkier launch unit from the ground and typically follows the target with a laser beam. The missile follows the laser beam until impact. While this method is more accurate and immune to many defense systems, the system has its limitations. The operator, in keeping the laser fixed on the target, is more susceptible to counter-attacks and has to keep both the missile and the target in his line of sight.

Anti-MANPADS Defense Systems

Both policy and technical developments have sought to mitigate the threat of MANPADS (5). By securing airport perimeters, terrorists with MANPADS can be kept out of range of aircrafts. Changing aircraft departure and approach patterns to a steep climb and a tight spiral down could minimize the amount of time that aircraft remain in range of MANPADS. However, the range of MANPADS is up to 15,000 feet from their launch point. Planes currently remain in range of MANPADS for 25 miles, and securing this area would be wildly expensive. Similarly, retraining pilots to adopt new departure and landing techniques would be expensive and also increase the likelihood of danger in the case of engine failure.

Technical countermeasures against MANPADS can either be classified as active or passive (4). Active countermeasures include systems that are triggered upon missile detection, such as flares. The steering mechanism of passive homing MANPADS pulls them towards infrared signals released by an airplane’s engines (6). Flares, which release a stronger infrared signal than the airplane itself, can misdirect MANPADS missiles. These active systems are comparatively cheap, but the flares are heavy, pushing up fuel costs, and a fire hazard, making them unattractive for commercial aircrafts (4). As anti-missile technology developed, missile technology followed suit. New missile designs included ultraviolet sensors to detect airplanes among their decoys, making flares ineffective.

Another alternative, called laser-based Direct Infrared Countermeasures (DIRCM), attack the infrared sensors themselves (6). On board the aircraft would be a lamp or laser system that, upon detecting an incoming missile, will direct intense infrared energy towards the missile. The missile’s infrared sensor would be overpowered and left unable to track the aircraft. However, this system also struggled to keep up with developments in MANPADS design. They offer protection against most generations of MANPADS, but they need to remain up to date with new seeker models. The protective system could otherwise fail to destroy the seeker and instead become a clearer infrared target.

Development of Commercial Systems

In 2004, the Department of Homeland Security (DHS) began a 4 year study on adapting anti-MANPADS systems for commercial aircrafts. Two aerospace defense corporations, BAE Systems and Northrop Grumman (NG) participated in the study to woo DHS for the defense contract.

NG equipped 11 regularly used FedEx cargo aircraft with its Guardian anti-missile system (8). As pictured in Fig 3., NG consolidated their system into a pod that could attach to the bottom of any airplane (9). NG’s Guardian system was relatively cheap at a million dollars per plane after the two hundredth or three hundredth airplane compared to DHS’s cost requirement of a million dollars per plane after the thousandth airplane. Both NG’s Guardian and the BAE’s Jeteye systems used laser-based Direct Infrared Countermeasures (DIRCM).

In December 2008, the Department of Homeland Security ultimately signed with BAE systems for $29 million (10). Seven months later, DHS announced that an American Airlines Boeing 767 had been outfitted with the BAE Jeteye infrared missile defense system and that the aircraft had just completed its first flight — from JFK to LA. The design for Jeteye was based on systems used in military aircrafts and involved seeker-jamming laser systems (11). DHS then sought to outfit two more AA 767s with Jeteye in order to confirm the system’s sustainability and reliability.

Abandoning the March

The costs of the defense systems proved to be their downfall. Fitting an airplane with such systems can cost between one to four million USD, along with $300,000 each year in operating costs (4). Fitting all U.S. commercial aircrafts with anti-MANPADS would cost about $43 billion over 20 years, so in 2010, the U.S. government ended its funding (3). $276 million had been spent over eight years to research and develop these systems.

Given that there have been no instances of MANPADS attacks on U.S. soil, committing further funding to this nebulous threat is difficult for the government to justify, and some experts also argue that, as a result of the current levels of pilot training as well as the robustness of newer aircraft models, the threat of MANPADS is limited (4).

However, even the million-dollar price tag for each system is not much in the world of aviation; in-flight entertainment systems for aircraft cost three million dollars on average (12). The threat of MANPADS is real but remains largely theoretical, paling in the face of the hundreds of other risks on the DHS’s tab. In the future, the choices about protecting America may lie not with the Department of Homeland Security but with commercial airliners. They will be the ones determining what their passengers truly need.

Contact Shinri Kamei at



1. Kenya Terror Strikes Target Israelis (2002). Available at: http://news.bbc.co.uk/2/hi/africa/2522207.stm (22 August 2013).

2. D. Kimball, MANPADS at a Glance (2013). Available at: http://www.armscontrol.org/factsheets/manpads (23 August 2013).

3. R. Tiron, Congress Stops Funding Commercial Airline Defense Tech (2010). Available at: http://www.popularmechanics.com/technology/military/missile-defense/manpads-airplane-missile-defense (23 August 2013).

4. M. Ashkenazi et. al., “Brief 47: MANPADS A Terrorist Threat to Civilian Aviation?” (Bonn International Center for Conversion, Bonn, NY, 2013; http://www.bicc.de/uploads/tx_bicctools/BICC_brief_02.pdf).

5. Man-Portable Air Defense System (MANPADS) Proliferation (2013). Available at: http://www.fas.org/programs/ssp/asmp/MANPADS.html (16 September 2013).

6. Australian Government Department of Foreign Affairs and Trade, Man-Portable Air Defence Systems (MANPADS) Countering the Terrorist Threat (Australian Strategic Policy Institute, 2008; http://www.dfat.gov.au/security/manpads_countering_terrorist_threat.pdf).

7. BAE Jeteye Anti-Manpads System Installed on American Airlines Plane (2008). Available at: http://www.satellitetoday.com/publications/st/2008/07/28/bae-jeteye-anti-manpads-system-installed-on-american-airlines-plane/ (10 September 2013).

8. J. Doyle, BAE, NG Bid to Test counter-MANPADS on Airliners (2007). Available at: http://abcnews.go.com/Technology/story?id=3603787&page=1 (10 September 2013).

9. M. McCarter, Northrop Grumman Completes C-MANPADS Tests (2008). Available at: http://www.hstoday.us/briefings/industry-news/single-article/northrop-grumman-completes-c-manpads-tests/6e65a2af6aab849669b11b64900a41d6.html (10 September 2013).

10. M. Ahlers, Anti-missile system to be tested on passenger planes (2008). Available at: http://edition.cnn.com/2008/TRAVEL/01/04/missile.tests/ (10 September 2013).

11. C. Howard, BAE Systems applies military technology to commercial airliner defense system (2006). Available at: http://www.militaryaerospace.com/articles/print/volume-17/issue-10/news/bae-systems-applies-military-technology-to-commercial-airliner-defense-system.html (10 September 2013).

12. S. Schechner, Airlines Entertain Tablet Ideas (2012). Available at: http://online.wsj.com/article/SB10000872396390443916104578020601759253578.html (10 September 2013).

13. Short Range SAM Divison, MANPADS Components. Available at: http://www.fas.org/irp/dia/manpads_components.pdf (16 September 2013).