Grid fin

The Vympel NPO R-77 is a beyond-visual-range missile that uses grid fins. The gray KAB-500 OD guided bomb on the left of the image has conventional "planar" tail fins.
Closeup of MOAB grid fins

Grid fins (or lattice fins) are a type of flight control surface used on rockets and bombs, sometimes in place of more conventional control surfaces, such as planar fins. They were developed in the 1950s by a team led by Sergey Belotserkovskiy [ru][1] and used since the 1970s in various Soviet ballistic missile designs such as the SS-12 Scaleboard, SS-20 Saber, SS-21 Scarab, SS-23 Spider, and SS-25 Sickle, as well as the N-1 (the intended rocket for the Soviet moon program). In Russia, they are thus often referred to as Belotserkovskiy grid fins.

Grid fins have also been used on conventional missiles and bombs such as the Vympel R-77 air-to-air missile; the 3M-54 Klub (SS-N-27 Sizzler) family of cruise missiles; and the American Massive Ordnance Air Blast (MOAB) large-yield conventional bomb, and on specialized devices such as the Quick-MEDS delivery system and as part of the launch escape system for the Soyuz spacecraft.

In 2014, SpaceX tested grid fins on a first-stage demonstration test vehicle of its reusable Falcon 9 rocket,[2] and on December 21, 2015 they were used during the high-velocity atmospheric portion of the reentry to help guide a commercial Falcon 9 first stage back to land for the first successful orbital booster landing in spaceflight history.

The 1st stage of the private Chinese company i-Space's Hyperbola-1 rocket appeared on July 25, 2019 to be equipped with steerable grid fins for attitude control.

On July 25, 2019, China launched a modified version of Long March 2C which featured grid fins atop the first stage for controlled re-entry of the spent rocket stage away from people in nearby towns and cities.[3]

  1. ^ Редакция журнала "Наука и жизнь" (Editorial staff of the journal "Science and Life") (April 1998). ТРУДНЫЙ ВЗЛЕТ РЕШЕТЧАТЫХ КРЫЛЬЕВ [The difficult take-off of lattice wings]. www.nkj.ru. Archived from the original on 2019-07-26. Retrieved 2021-10-01.
  2. ^ "F9R 1000m Fin Flight | Onboard Cam and Wide Shot". SpaceX. 2014. Archived from the original on 14 August 2018. Retrieved 21 June 2014 – via YouTube.
  3. ^ Jones, Andrew (30 July 2019). "Chinese Long March launch tests grid fins for safety, future reusability". SpaceNews.com.