Parts · Flight controls

Servo

219 failure reports named the servo in the last ten years, 1,314 since 1995, most often on the Boeing 737; the condition most often found was "leaking". 23 FAA approvals let 10 companies make a replacement servo, Trio Avionics Corporation holding the most (8). The reports call it "servo", "servo assy".

Reports by year

Reports by year, as a table

	reports
1995	51
1996	33
1997	36
1998	27
1999	74
2000	79
2001	85
2002	60
2003	88
2004	75
2005	60
2006	62
2007	39
2008	38
2009	26
2010	40
2011	54
2012	61
2013	55
2014	32
2015	20
2016	33
2017	23
2018	14
2019	40
2020	8
2021	19
2022	13
2023	13
2024	24
2025	29
2026	3

Which system the reports file it under last ten years

Flight controls116Engine38Rotorcraft systems38Fuel system10Heating, ice protection and utility systems7Landing gear5Airframe structure5

Reports by system, as a table

	reports
Flight controls	116
Engine	38
Rotorcraft systems	38
Fuel system	10
Heating, ice protection and utility systems	7
Landing gear	5
Airframe structure	5

Models most often reporting it last ten years

Boeing 73734Airbus A32020Robinson R4419Cessna 172 Skyhawk17Airbus A31914Boeing 76714Sikorsky S-9212Bombardier CL-600 Challenger and CRJ7Piper PA-28 Cherokee, Warrior, Archer and Arrow6Airbus Helicopters AS350 AStar (Écureuil), now H1255Embraer ERJ 170 E170 and E1755Cessna 208 Caravan4

Models most reported, as a table

	reports
Boeing 737	34
Airbus A320	20
Robinson R44	19
Cessna 172 Skyhawk	17
Airbus A319	14
Boeing 767	14
Sikorsky S-92	12
Bombardier CL-600 Challenger and CRJ	7
Piper PA-28 Cherokee, Warrior, Archer and Arrow	6
Airbus Helicopters AS350 AStar (Écureuil), now H125	5
Embraer ERJ 170 E170 and E175	5
Cessna 208 Caravan	4

How it failed the condition found, last ten years

leaking51failed33faulted16malfunctioned15contaminated13defective11faulty11inoperative8worn8abnormal5

Conditions found, as a table

	reports
leaking	51
failed	33
faulted	16
malfunctioned	15
contaminated	13
defective	11
faulty	11
inoperative	8
worn	8
abnormal	5

Engines most often reporting it

Lycoming O-540-F1B5 10Lycoming IO-360-L2A 9Lycoming IO-540-AE1A5 8CFM International CFM56-7B27E 6Lycoming IO-360-M1A 4Turbomeca (Safran) ARRIEL 2B1 3CFM International CFM56-7B27 2CFM International CFM56-7B27/B3 2CFM International CFM56 series 2Lycoming IO-360-B4A 2

Approved replacement parts 23 parts manufacturer approvals

A parts manufacturer approval (PMA) lets a company other than the aircraft's maker make a servo and sell it as an approved part for the models named. These are the companies holding such approvals for a servo:

Trio Avionics Corporation 8Ontic Engineering & Manufacturing INC 4Rotair Industries INC 3Aviation Materials Management INC 2Woodward Hrt INC 1Triumph Thermal Systems INC 1Parker Hannifin CORP 1Honeywell International INC. 1Aviation Materials Management, INC. 1Aviation Materials Management, INC 1

For these models most: Boeing 737 (8), Cessna 182 Skylane (4), Sikorsky S-61 (3), Piper PA-28 Cherokee, Warrior, Archer and Arrow (2), Cessna TR182 Turbo Skylane RG (2), Cessna T182 Turbo Skylane (2), Cessna R182 Skylane RG (2), Cessna 177 Cardinal (2), Cessna 172 Skyhawk (2), Douglas DC-9 (1), Boeing 707 (1).

Maker	Part	Replaces	Fits	Granted	Status
Honeywell International INC.	Servo 107458-1	107458-1	Boeing 707-300 Series	2023-01-09	current
Trio Avionics Corporation	Servo, Roll or Pitch, CW Rotation 30000000	30000000	Piper Aircraft, Inc. PA-28-140, PA-28-151, PA-28-150	2018-03-04	current
Trio Avionics Corporation	Servo, Roll or Pitch, CW Rotation 30000000	30000000	Textron Aviation Inc. 177, 177A, 177B	2018-03-04	current
Trio Avionics Corporation	Servo, Roll or Pitch, CW Rotation 30000000	30000000	Textron Aviation Inc. 182, 182A, 182B	2018-03-04	current
Trio Avionics Corporation	Servo, Roll or Pitch, CCW Rotation 31000000	31000000	Textron Aviation Inc. 177, 177A, 177B	2018-03-04	current
Trio Avionics Corporation	Servo, Roll or Pitch, CCW Rotation 31000000	31000000	Textron Aviation Inc. 182, 182A, 182B	2018-03-04	current
Trio Avionics Corporation	Servo, Roll or Pitch, CCW Rotation 31000000	31000000	Piper Aircraft, Inc. PA-28-140, PA-28-151, PA-28-150	2018-03-04	current
Trio Avionics Corporation	Servo, Roll or Pitch, CCW Rotation 31000000	31000000	Textron Aviation Inc. 172, 172A, 172B	2017-08-13	current
Trio Avionics Corporation	Servo, Roll or Pitch, CW Rotation 30000000	30000000	Textron Aviation Inc. 172, 172A, 172B	2017-08-13	current
Aviation Materials Management, INC	Servo Assy 251A2170-1	251A2170-1	Boeing 737-600 Series, 737-700 Series,...	2015-02-12	current
Aviation Materials Management, INC.	Servo Assy 251A2170-1	251A2170-1	Boeing 737-600 Series, 737-700 Series,...	2014-09-04	current
Aviation Materials Management INC	Servo Assy 251A2170-1	251A2170-1	Boeing 737-600 Series, 737-700 Series,...	2013-02-26	current
Aviation Materials Management INC	Servo Assy 251A2170-1	251A2170-1	Boeing 737-600 Series, 737-700 Series,...	2010-10-05	current
Woodward Hrt INC	Servo, Pilot 1056350-9A	1056350-9A	Douglas DC9-11, -14, -15	2009-06-29	current
Ontic Engineering & Manufacturing INC	Servo, Rotary Stabilizer Trim 56019-005	10-61472-5	Boeing 737-100 Series, 737-200 Series,...	2007-05-14	current
Ontic Engineering & Manufacturing INC	Servo, Rotary Stabilizer Trim 56019-003	10-61472-4	Boeing 737-100 Series, 737-200 Series,...	2007-05-14	current
Ontic Engineering & Manufacturing INC	Servo, Rotary Stabilizer Trim 56019-005	10-61472-5	Boeing 737-100 Series, 737-200 Series,...	2007-01-10	current
Ontic Engineering & Manufacturing INC	Servo, Rotary Stabilizer Trim 56019-003	10-61472-4	Boeing 737-100 Series, 737-200 Series,...	2007-01-10	current
Triumph Thermal Systems INC	Servo/Fuel Heat Exchanger UA538950-8	GE Aircraft Engines P/N: 1962M36P01	General Electric CF6-80A, CF6-80A2, CF6-80C2	2003-11-20	current
Parker Hannifin CORP	Servo/Oil Heat Exchanger UA538950-8	1962M36P01	General Electric CF6-80A, CF6-80C2, CF6-80E1	2002-08-04	current
Rotair Industries INC	Servo Assembly R61070-98013-043	61070-98013-043	Sikorsky S61A/L/N/NM/R	1997-12-12	current
Rotair Industries INC	Servo Assembly R61070-98013-042	61070-98013-042	Sikorsky S61A/L/N/NM/R	1997-12-12	current
Rotair Industries INC	Servo Assembly R61070-98013-041	61070-98013-041	Sikorsky S61A/L/N/NM/R	1997-12-12	current

Sources: the FAA's service difficulty reports since 1995 (a report is a part that failed and was fixed, as filed by an airline, repair station or owner; the count shows reporting as much as reliability) and the parts manufacturer approvals in the FAA's Dynamic Regulatory System. The part name is the reporters' and the approval holders' own words, reduced to the first plain words so that spellings meet.