Business Aviation Compliance With Pre Take-off Flight Control Checks

The US National Transportation Safety Board (NTSB) highlighted a number of important human performance issues in after a fatal Gulfstream G-IV N121JM business aircraft accident which occurred on 12 May 2014 at the joint civil/military Hanscom Field (BED) in Bedford, Massachusetts (final report).

Aerossurance has discussed that accident previously: Gulfstream G-IV Take Off Accident & Human Factors

This NTSB video illustrates the G-IV take off:

Wreckage of Gulfstream GIV N121JM at Bedford, MA (Credit: MSP via NTSB)

Wreckage of Gulfstream GIV N121JM at Bedford, MA (Credit: MSP via NTSB)

The NTSB determined that the probable cause of this accident was:

… the flight crewmembers’ failure to perform the flight control check before takeoff, their attempt to take off with the gust lock system engaged, and their delayed execution of a rejected takeoff after they became aware that the controls were locked.

Contributing to the accident were the flight crew’s habitual noncompliance with checklists, Gulfstream Aerospace Corporation’s failure to ensure that the G-IV gust lock/throttle lever interlock system would prevent an attempted takeoff with the gust lock engaged, and the Federal Aviation Administration’s failure to detect this inadequacy during the G-IV’s certification.

Aerossurance subsequently analysed a US Air Force (USAF) Lockheed Martin C-130J accident were a control check was omitted: C-130J Control Restriction Accident, Jalalabad

It is noteworthy that when the NTSB reviewed flight data from the aircraft’s Quick Access Recorder (QAR), they discovered that this flight crew had failed to perform complete flight control checks before 98% of their previous 175 take offs.  To the NTSB this indicated that this omission was “habitual”.  The NTSB describe this a procedural drift (a topic we have discussed in our recent article: ‘Procedural Drift’: Lynx CFIT in Afghanistan).

Among the NTSB recommendations was a recommendation to the National Business Aviation Association (NBAA):

Work with existing business aviation flight operational quality assurance groups, such as the Corporate Flight Operational Quality Assurance Centerline Steering Committee [a Flight Safety Foundation initiated initiative], to analyze existing data for non-compliance with manufacturer-required routine flight control checks before takeoff and provide the results of this analysis to your members as part of your data-driven safety agenda for business aviation.

The NBAA has now published their analysis report: Business Aviation Compliance With Manufacturer-Required Flight-Control Checks Before Takeoff

The [FDM] data [analysed] shows that out of 143,756 flights conducted during the 2013 to 2015 time period, flight crews [only] conducted a partial flight-control check before takeoff (caution event) during 22,458 flights (15.62 percent). There was no flight-control check before takeoff (warning event) conducted on 2,923 flights (2.03 percent). For the three-year period covering 2013, 2014 and 2015, the overall noncompliance rate for manufacturer-required routine flight-control checks before takeoff was 17.66 percent, reflecting 25,381 events.


After the accident on May 31, 2014, and the release of the preliminary report on June 13, 2014, the average warning event rate was reduced to 1.47 percent, a drop of 50 percent. That may indicate there was a positive reaction to the preliminary report finding that the Bedford crew did not perform any flight-control check before takeoff. The caution events are more variable, and there is not a significant difference in caution event rates between pre- and post-accident percentages.

This report to the NBAA membership is not only intended to provide closure action to the NTSB recommendation, but also to raise awareness to the broader business aviation community that complacency and lack of procedural discipline have no place in our profession.

NBAA President and CEO Ed Bolen said:

As perplexing as it is that a highly experienced crew could attempt a takeoff with the gust lock engaged, the data also reveals similar challenges across a variety of aircraft and operators. This report should further raise awareness within the business aviation community that complacency and lack of procedural discipline have no place in our profession.

While this study helps us understand compliance in business aviation, it is certainly noticeable that FDM data is already available that can be used to identify such habitual practices inconsistent with procedures.

In 1992 the gust locks had not been fully disengaged on a third-party DHC-4T Turbine Caribou conversion, N400NC, leading to a horrific fatal accident that killed 3.

UPDATE 27 September 2016: Bizav ‘Has Long Way To Go on Safety,’ Says NBAA Chief at the 20th annual Bombardier Safety Standdown in Wichita. Commenting after the their pre-flight flight control check report of the Ed Bolden said:

We have to understand the data and then find some way to move from reactive to proactive. If there’s a challenge, then we need to find a mitigation strategy. It’s an important and noble pursuit.

UPDATE 24 October 2016: Execuflight Hawker 700 N237WR Akron Accident: Casual Compliance A disturbing accident after an unstabilised approach that begs serious questions of the operator’s procedures and culture.

UPDATE 30 October 2016: LOC-I Departure: AAIB Report on King Air 200 Accident

UPDATE 7 May 2017: We also look at another case of poor checklist use: Ground Collision Under Pressure: Challenger vs ATV: 1-0

UPDATE 19 May 2018: If you had spent 2 years rebuilding a classic Piper PA-12 you’d make the time to check the rigging of the flying controls before first flight, right? Sadly, the pilot in this fatal case study was in a rush: Too Rushed to Check: Misrigged Flying Controls

UPDATE 9 July 2018: In a safety investigation report released last week, the TSB said that the operator of a survey Piper PA-31 Navajo C-FQQB, was unaware that the accident pilots “had frequently flown at very low altitudes” while transiting between survey areas and their base.  The Navajo was flying between 40 ft and 100 ft AGL when it struck power cables on 30 April 2017.  TSB reiterated a call for flight recorders on smaller aircraft.

UPDATE 17 November 2018: Investigation into F-22A Take Off Accident Highlights a Cultural Issue

UPDATE 31 May 2019: The Portuguese accident investigation agency, GPIAAF, issued a safety investigation update on a serious in-flight loss of control incident involving Air Astana Embraer ERJ-190 P4-KCJ that occurred on 11 November 2018.  The aircraft was landed safely after considerable difficulty, so much so the crew had debated ditching offshore.  GPIAAF conformed that incorrect ailerons control cable system installation had occurred in both wings during a maintenance check conducted in Portugal.

Misrigged Flying Control Cable, Air Astana Embraer EJ-190 P4-KCJ (Credit: GPIAFF)

Misrigged Flying Control Cable, Air Astana Embraer EJ-190 P4-KCJ (Credit: GPIAFF)

GPIAFF note that: “By introducing the modification iaw Service Bulletin 190-57-0038 during the maintenance activities, there was no longer the cable routing and separation around rib 21, making it harder to understand the maintenance instructions, with recognized opportunities for improvement in the maintenance actions interpretation”.  They also comment that: “The message “FLT CTRL NO DISPATCH” was generated during the maintenance activities, which in turn originated additional troubleshooting activities by the maintenance service provider, supported by the aircraft manufacturer. These activities, which lasted for 11 days, did not identify the ailerons’ cables reversal, nor was this correlated to the “FLT CTRL NO DISPATCH” message.”

GPIAFF comment “deviations to the internal procedures” occurred within the maintenance organisation that “led to the error not being detected in the various safety barriers designed” in the process.  They also note that the error ” was not identified in the aircraft operational checks (flight controls check) by the operator’s crew.”

UPDATE 1 June 2019: Our analysis: ERJ-190 Flying Control Rigging Error

UPDATE 8 June 2020: Fatal Falcon 50 Accident: Unairworthy with Unqualified Crew

UPDATE 4 October 2020: Investigators Suggest Cultural Indifference to Checklist Use a Factor in TAROM ATR42 Runway Excursion

Aerossurance is pleased to be sponsoring the Chartered Institute of Ergonomics & Human Factors‘ Human Factors in Aviation Safety conference at East Midlands Airport 7-8 November 2016.

Aerossurance has extensive air safety, aircraft certification and accident analysis experience.  If you charter or operate your own business aircraft, Aerossurance can provide assurance of those operation and advise on best practice.  Contact us at: