In normal flight, maneuvering an aircraft requires some combination of controls, which are often interactive in their effect.
A basic means of controlling an aircraft with disabled flight controls is making use of the position of the engines. If the engines are mounted under the centre of gravity, as in underwing passenger jets, then increasing the thrust will raise the nose while decreasing the thrust will lower it. This control method may call for control inputs that go against the pilot's instinct: when the aircraft is in a dive, adding thrust will raise the nose and vice versa.
Additionally, asymmetrical thrust has been used for directional control: if the left engine is idled and power is increased on the right side this will result in a yaw to the left, and vice versa. If throttle settings allow the throttles to be shifted without affecting the total amount of power, then yaw control can be combined with pitch control. If the aircraft is yawing, then the wing on the outside of this yaw movement will go faster than the inner wing. This creates higher lift on the faster wing, resulting in a rolling movement, which helps to make a turn.
Controlling airspeed has been shown to be very difficult with engine control only, often resulting in a fast landing. A faster than normal landing also results when the flaps cannot be extended due to loss of hydraulics.
Another challenge for pilots who are forced to fly an aircraft without functioning control surfaces is to avoid the phugoid instability mode (a cycle in which the aircraft repeatedly climbs and then dives), which requires careful use of the throttle.
Because this type of aircraft control is difficult for humans to achieve, researchers have attempted to integrate this control ability into the computers of fly-by-wire aircraft. Early attempts to add the ability to real aircraft were not very successful, the software having been based on experiments conducted in flight simulators where jet engines are usually modelled as "perfect" devices with exactly the same thrust on each engine, a linear relationship between throttle setting and thrust, and instantaneous response to input. More modern computer systems have been updated to account for these factors, and aircraft have been successfully flown with this software installed.1 However, it remains a rarity on commercial aircraft.
Incidents where disabled, damaged, and/or failed control systems were a significant or primary cause of the accident.
In these incidents, a failure of propulsion systems (engine, fan, propeller, pumps) caused damage to control systems. (Engine mounting failures are covered under structural failures, below.)
In these incidents, a failure of structural components (bulkheads, doors, struts, mounts, spars, hull) subsequently damaged control systems.
In these incidents, there was a failure of control system components themselves (e.g. cables, hydraulics, flaps, slats, ailerons, rudder, stabilizer, trim tabs, auto-pilot). (Control system fatigue failures are here, but improperly installed or incorrectly adjusted controls in the next section.)
In these incidents, the failure of control system components was caused by improper installation or adjustment of control systems components by maintenance personnel.
In these incidents, pilot error resulted in control system damage.
These incidents describe mid-air collisions that mainly damaged control systems of at least one of the aircraft, which may or may not have been recoverable.
In the Charlie Brown and Franz Stigler incident on 20 December 1943, a Boeing B-17F Flying Fortress of the 527th Bombardment Squadron was tasked with carrying out a bomb run on Bremen, Germany, in formation with other B-17Fs. Before the bomber released its bomb load, accurate flak shattered the Plexiglas nose, knocked out the #2 engine and further damaged the #4 engine, which was already in questionable condition and had to be throttled back to prevent overspeeding. This caused the plane to fall back from the formation and left it vulnerable to enemy attack. The B-17F was then attacked by over a dozen enemy fighters (a combination of Messerschmitt Bf 109s and Focke-Wulf Fw 190s) of JG 11 for more than ten minutes, causing the pilot to lose consciousness and putting the B-17F into a steep dive. The pilot later regained consciousness and recovered the plane from the dive. Further damage was sustained from the attack, including to the #3 engine, reducing it to only half power (meaning the aircraft had effectively, at best, 40% of its total rated power available). The bomber's internal oxygen, hydraulic, and electrical systems were also damaged, and the bomber had lost half of its rudder and port elevator, as well as its nose cone. The crew on board were also wounded with one of them being killed. After being escorted by a Luftwaffe Messerschmitt Bf 109 G-6 to be out of German airspace, the B-17F landed at RAF Seething.24252627
On October 10, 1928, U.S. Army photographer Albert William Stevens and Captain St. Clair Streett, the chief of the U.S. Army Air Corps Materiel Division's Flying Branch, flew the XCO-5 experimental biplane to achieve an unofficial altitude record for aircraft carrying more than one person: 37,854 feet (11,538 m); less than 1,000 feet (300 m) short of the official single-person altitude record.33 Stevens snapped photographs of the ground below, warmed by electrically heated mittens and many layers of clothing. At that height the men measured a temperature of −78 °F (−61 °C), cold enough to freeze the aircraft controls.34 When Stevens was finished with his camera, Streett found that the aircraft's controls were rendered immobile in the cold, with Streett unable to reduce throttle for descent. The aircraft's engine continued to run at the high power level necessary for maintaining high altitude. Streett contemplated diving at full power, but the XCO-5 was not built for such strong maneuvers—its wings could have sheared off. Instead, Streett waited until fuel was exhausted and the engine sputtered to a stop, after which he piloted the fragile aircraft down in a gentle glide and made a deadstick landing.35 An article about the feat appeared in Popular Science in May 1929, entitled "Stranded—Seven Miles Up!"36
NASA personnel at Dryden Flight Research Center worked on the design of an aircraft control system using only thrust from its engines. The system was first tested on a McDonnell Douglas F-15 Eagle in 1993, piloted by Gordon Fullerton.38 The system was then applied to a McDonnell Douglas MD-11 airliner, and Fullerton made its first propulsion-controlled landing in August 1995.39 Later flights were made with the center engine at idle speed so the system could be tested using the two wing-mounted engines, simulating the more common airliner layout.40
"Active Home Page". Past Research Projects. NASA. Archived from the original on September 30, 2006. Retrieved June 1, 2006. https://web.archive.org/web/20060930191203/http://www1.nasa.gov/centers/dryden/history/pastprojects/Active/index.html ↩
"Aircraft Accident Report" (PDF). Archived from the original on June 15, 2011. Retrieved May 6, 2014. https://web.archive.org/web/20110615031242/http://www.airdisaster.com/reports/ntsb/AAR82-05.pdf ↩
"DCA83AA029". Ntsb.gov. June 8, 1983. Retrieved March 8, 2014. https://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20001214X43286 ↩
Gero 1997, p. 199. ↩
Gero 1997, p. 210. ↩
"The monument on the site of the crash of Flight 130 | memorial". Wikimapia.org. January 3, 1994. Retrieved March 8, 2014. http://wikimapia.org/24202438/The-monument-on-the-site-of-the-crash-of-Flight-130 ↩
Gero 1997, p. 125. ↩
"Accident Details". Accident to Turkish Airlines DC-10 TC-JAV in the Ermenonville Forest on 3 March 1974 Final Report Archived 2 June 2011 at the Wayback Machine. French State Secretariat for Transport. 1. Retrieved on 13 February 2011. http://www.aaib.gov.uk/cms_resources.cfm?file=/8-1976%20TC-JAV.pdf ↩
"The Saving Of Flight 1080". Washington Post. October 8, 1978. ISSN 0190-8286. Retrieved May 19, 2018. https://www.washingtonpost.com/archive/opinions/1978/10/08/the-saving-of-flight-1080/bc18f021-691d-4b19-8041-dc03a089bf6d/ ↩
Gero 1997, p. 189. ↩
Flight 961 – Official accident report. www.bst.gc.ca Retrieved: 1 June 2010 http://www.bst.gc.ca/eng/rapports-reports/aviation/2005/a05f0047/a05f0047.pdf ↩
Ranter, Harro. "ASN Aircraft accident Embraer ERJ-190LR (ERJ-190-100 LR) P4-KCJ Lisbon". aviation-safety.net. Retrieved September 18, 2022. https://aviation-safety.net/database/record.php?id=20181111-0 ↩
"Loss of Pitch Control During Takeoff Air Midwest Flight 5481 Raytheon (Beechcraft) 1900D, N233YV Charlotte, North Carolina January 8, 2003" (PDF). Retrieved March 8, 2014. https://www.ntsb.gov/doclib/reports/2004/AAR0401.pdf ↩
Flight 934 – Aviation Safety Network aviation-safety.net Retrieved: 1 June 2010. http://aviation-safety.net/database/record.php?id=19941210-0 ↩
Aviation Safety Network aviation-safety.net Retrieved: 1 June 2010. http://aviation-safety.net/database/record.php?id=20031122-0 ↩
"Growing evidence suggests Azerbaijan Airlines flight was targeted by missile strike". Türkiye Today. December 25, 2024. Retrieved December 25, 2024. https://www.turkiyetoday.com/world/growing-evidence-suggests-azerbaijan-airlines-flight-was-targeted-by-missile-strike-97513/ ↩
National Transportation Safety Board (24 May 1972), Aircraft Accident Report[usurped], retrieved 27 March 2014 /wiki/National_Transportation_Safety_Board ↩
Ranter, Harro. "ASN Aircraft accident Boeing 727-2J0 (F) Advanced HK-4544 Puerto Carreño-Germán Olano Airport (PCR)". aviation-safety.net. Retrieved September 2, 2022. https://aviation-safety.net/database/record.php?id=20161220-0 ↩
"Crash: Aerosucre B722 at Puerto Carreno on Dec 20th 2016, overran runway on takeoff". avherald.com. Retrieved September 2, 2022. https://avherald.com/h?article=4a25fb25&opt=0 ↩
Not including experimental flights ↩
The number of fatalities vary depending on the source, but official accounts state 138 of 314 on board were killed. ↩
"Last Flight From Saigon". USAF Southeast Asia Monograph Series. IV. Diane Publishing: 29. 1978. ISBN 1-4289-8211-6. 1-4289-8211-6 ↩
Ranter, Harro. "ASN Aircraft accident Lockheed C-5A Galaxy 68-0218 Saigon-Tan Son Nhat International Airport (SGN)". aviation-safety.net. Retrieved August 19, 2022. https://aviation-safety.net/database/record.php?id=19750404-0 ↩
"Chivalry in the Air – Chivalry Today". Retrieved August 20, 2022. https://chivalrytoday.com/chivalry-air/ ↩
Makos & Alexander 2012, pp. 181, 184–85. - Makos, Adam; Alexander, Larry (2012). A Higher Call: An Incredible True Story of Combat and Chivalry in the War-Torn Skies of World War II (1st ed.). New York: Berkley Caliber. ISBN 978-0-425-25286-4. ↩
John Blake. "Two enemies discover a 'higher call' in battle". CNN. Retrieved August 20, 2022. https://www.cnn.com/2013/03/09/living/higher-call-military-chivalry/index.html ↩
tara (December 21, 2020). "This Day in History: The Charlie Brown & Franz Stigler incident". Taraross. Retrieved August 20, 2022. https://www.taraross.com/post/tdih-brown-stigler-incident ↩
"Commentary - A new perspective on a challenging day at work". August 7, 2016. Archived from the original on August 7, 2016. Retrieved September 1, 2022. https://web.archive.org/web/20160807134932/http://www.charleston.af.mil/news/story.asp?id=123438088 ↩
Leone, Dario (November 9, 2017). "THE STORY OF "ALL AMERICAN", THE B-17 THAT MADE IT HOME AFTER HAVING BEEN SLICED BY THE WING OF AN Me 109". The Aviation Geek Club. Retrieved September 1, 2022. https://theaviationgeekclub.com/story-american-b-17-made-home-sliced-wing-109/ ↩
WarbirdsNews (June 27, 2013). "WWII's B-17 "All American" Separating Fact and Fiction". Vintage Aviation News. Retrieved September 1, 2022. https://warbirdsnews.com/warbird-articles/wwiis-b-17-all-american-separating-fact-fiction.html ↩
B17 All American ~ (Rev. 2a) (720p HD), retrieved September 1, 2022 https://www.youtube.com/watch?v=_OAPgo1iUvM ↩
National Aeronautics and Space Administration. Aeronautics and Astronautics Chronology, 1925–1929. Retrieved on January 3, 2010. https://history.nasa.gov/Timeline/1925-29.html ↩
Armagnac, Alden P. Popular Science, May 1929. "Stranded—Seven Miles Up!" Retrieved on November 22, 2009. https://books.google.com/books?id=bCoDAAAAMBAJ&pg=PA22 ↩
"Transiting from Air to Space". History.nasa.gov. Retrieved March 8, 2014. https://history.nasa.gov/hyperrev-x15/ch-6.html ↩
"MD-11 Propulsion Controlled Aircraft (PCA)". www.nasa.gov. Retrieved May 16, 2021. https://www.nasa.gov/centers/dryden/multimedia/imagegallery/MD-11PCA/MD-11PCA_proj_desc.html ↩
Tucker, p. 29. ↩