Missile lofting

  1. Home
  2. Wiki

Lofting, sometimes referred to as "trajectory shaping",[1] is a trajectory optimization technique used in some missile systems to extend range and improve target engagement effectiveness, usually in beyond-visual range scenarios.[2]

A US-Navy Grumman F-14A Tomcat of VF-11 launches an AIM-54 Phoenix missile, in 1982

Method

[edit]

Lofting involves a missile ascending to a higher altitude after launch,[3] creating a parabolic arc similar to ballistic missiles, before descending toward its target. This elevated flight path allows the missile to capitalize on reduced air resistance at higher altitudes, increasing both the missile's potential energy and the kinetic energy during terminal guidance, thus enabling greater range and probability of kill.[4]

Peak altitiude of a lofted trajectory can be at altitudes ranging from 20,000–110,000 ft (6–34 km), with most air-to-air missiles peaking at around 80,000–100,000 ft (24–30 km),[2][5] although the peaks of ballistic missiles' parabolic arcs can range from 50 km (164,042 ft) to 1,500 km (4,921,260 ft).[6]

Advantages

[edit]

Lofting offers several distinct advantages compared to sea-skimming and direct-intercept trajectories, particularly in beyond-visual-range engagements.

Unlike sea-skimming, which prioritizes low-altitude flight to avoid radar detection but suffers from increased drag and limited range, lofting allows the missile to ascend to higher altitudes where air resistance is lower. This reduced drag enables greater range and energy efficiency, allowing the missile to retain more kinetic energy for terminal guidance and target interception.[2]

Compared to direct-intercept trajectories, lofting also improves engagement flexibility by providing a steeper attack angle, which is particularly effective against maneuvering or high-altitude targets.

Disadvantages

[edit]

In comparison to sea-skimming trajectories, lofting lacks radar-avoidance characteristics, making it susceptible to detection by its target and potential interceptors.

Lofting is also more mathematically and technologically complex in comparison to direct-interception, and is only viable in long-range engagements.

Additionally, the thinner air which lofting utilizes to reduce drag and increase range carries the downside of impeding the ability for control surfaces to maneuver the missile. This can reduce a missile's ability to adjust for fast-moving or maneuvering targets, however can be circumvented with the use of thrust vectoring - at the downside of added cost and complexity.

Use in Missiles

[edit]

A number of missiles are known or speculated to utilize lofting techniques, such as:

See also

[edit]

References

[edit]
  1. ^ Coté, Gilbert; Naval Education and Training Program Development Center (1981). Fire Control Technician M 3 (NAVEDTRA 10224). United States: Naval Education and Training Command via United States Government Printing Office. p. 2-19. SPARROW[…] utilizes trajectory shaping to greatly increase its performance envelope.
  2. ^ a b c Shin, Minjae; Tahk, Min-Jea; Kim, Boseok; Lee, Chang-Hun (2024). "PURSUIT-BASED LONG-RANGE AIR-TO-AIR MISSILE MIDCOURSE GUIDANCE ROBUST TO CHANGES IN THE PREDICTED IMPACT POINT" (PDF). International Congress of the Aeronautical Sciences: 3. Archived from the original (PDF) on 30 April 2025. 1 Quadratic polynomial[, peak altitude:] 33 km[;] 2 4th-order polynomial[, peak altitude:] 30 km[;] 3 4th-order polynomial[, peak altitude:] 25 km
  3. ^ Berglund, Erik; Licata, William (July 2001). Technologies for Future Precision Strike Missile Systems (ADA394520; RTO-EN-018; AC/323, SCI-087 bis; TP/37). Swedish Defence Research Agency & Raytheon Corporation (Report). BP 25, 7 rue Ancelle, F-92201 Neuilly-sur-Seine Cedex, France: Research and Technology Organization of the North Atlantic Treaty Organization. p. 2-3. Archived from the original (PDF) on 20 October 2025. Flight trajectory shaping is particularly beneficial for high performance supersonic missiles, which have large propellant or fuel weight fraction. To take advantage of flight trajectory shaping, the missile must rapidly pitch up and climb to an efficient cruise altitude. During the climb, the missile angle-of-attack should be small, to minimize drag.{{cite report}}: CS1 maint: location (link)
  4. ^ Berglund, Erik; Licata, William (July 2001). Technologies for Future Precision Strike Missile Systems (ADA394520; RTO-EN-018; AC/323, SCI-087 bis; TP/37). Swedish Defence Research Agency & Raytheon Corporation (Report). BP 25, 7 rue Ancelle, F-92201 Neuilly-sur-Seine Cedex, France: Research and Technology Organization of the North Atlantic Treaty Organization. p. 3-1. Archived from the original (PDF) on 20 October 2025. Air-to-air missiles often employ trajectory optimisation during the mid-course. The main reason for this is to exploit the lower drag at higher altitude. Optimisation can be used to obtain minimal time of flight, maximal range, maximal terminal velocity etc.{{cite report}}: CS1 maint: location (link)
  5. ^ a b Karon (2019-08-29). "AIM-54 and AWG-9 WCS: Observations about Lofted Trajectory and Range". FlyAndWire. Retrieved 2024-12-25.
  6. ^ "Prediction of Possible Intercept Time by Considering Flight Trajectory of Nodong Missile" (PDF). www.koreascience.or.kr. Archived from the original (PDF) on 2024-09-04. Retrieved 2024-12-29.
  7. ^ Department of the Air Force (1 July 1989). FLIGHT MANUAL USAF SERIES F-15A/B/C/D BLOCK 7 AND UP (TO 1F-15A-1). United States Department of Defense. pp. 1–64E. Archived from the original on 30 April 2024. Retrieved 6 September 2025. RLOFT (AIM-7MH)
  8. ^ Coté, Gilbert; Naval Education and Training Program Development Center (1981). Fire Control Technician M 3 (NAVEDTRA 10224). United States: Naval Education and Training Command via United States Government Printing Office. p. 2-19. SPARROW[…] utilizes trajectory shaping to greatly increase its performance envelope.
  9. ^ Barrie, Douglas. "Air-to-air warfare: speed kills". IISS Military Balance Blog. International Institute for Strategic Studies. Archived from the original on 9 September 2025. Retrieved 2025-10-21. The AIM-120D3 range extension is provided by trajectory shaping rather than by any solid motor modification. While this will give the missile a greater maximum range, the amount of energy it has when it reaches the target also remains important.
  10. ^ "Strategic Digest, Volume 32, Issues 6–12". Strategic Digest. 32 (6–12). India: Institute for Defence Studies and Analyses: 1189. 2002. Archived from the original on 24 August 2025. Retrieved 2 September 2025. Weapons such as the US AIM-120 AMRAAM can climb shortly after launch to high altitude, thus extending the range...
  11. ^ Barrie, Douglas (29 January 2024). "Air-to-air missiles push the performance, payload envelope". IISS Online Analysis. International Institute for Strategic Studies. Archived from the original on 13 August 2025. Retrieved 16 October 2025. The PL-17 (CH-AA-X-12) likely has a range of around 400 kilometres, using a dual-pulse solid rocket motor combined with a lofted trajectory to achieve the distance.