Aircraft Accidents and Lessons Unlearned XVII: Ryan Air Service 103

On November 23, 1987, Ryan Air Service flight 103 crashed on approach into Homer airport in Homer, Alaska; the Beech 1900C, registration number N401RA, was operating as a regularly scheduled Title 14 Code of Federal Regulations (CFR) Part 135 flight operation from Kodiak, Alaska to Homer.  The aircraft was not equipped with a flight data recorder or a cockpit voice recorder.

There were many reasons the flight crashed, but the most obvious factor was never addressed: Culture.  Even less attention was devoted to useful recommendations.

NOTE: When speaking of both weight and balance (W&B) or center of gravity (CG), the basics need to be understood.  Every aircraft has a CG envelope for flight, a specific range at the wings; it has a forward limit and an aft limit.  Any CG that falls forward of the envelope’s forward limit causes an imbalance resulting in a ‘nose heavy’ condition instability; any CG that falls aft of the envelope’s aft limit causes an imbalance resulting in a ‘tail heavy’ condition instability.  The calculated CG for any flight MUST fall between the forward and aft CG limits – for the entire flight – to maintain stability.

W&B is how one determines the flight’s CG; since every flight is different, every W&B calculation varies, while the envelope stays the same.  Where weights, e.g. passengers, fuel, baggage, are placed along the longitudinal and lateral axis of the aircraft to establish where the CG is for takeoff and where it ends up at the end of the flight.  The difference between Takeoff Gross Weight (TOGW) and Landing Weight, is the usable fuel that the aircraft burns as it flies.  In most aircraft, e.g. the Beech 1900C, as fuel is burned off, the CG moves aft because the used fuel at departure had brought the CG forward.

The National Transportation Safety Board (NTSB) found:

3/8 inch of ice had accumulated on the wings’ leading edges: It is unclear how ice thickness was determined; the aircraft descended quickly in a flat attitude, impacted terrain before sliding to a stop on its belly; there was no fire; although conditions favored icing, the impact would have affected the amount of ice clinging to the wings.  As to flight characteristics, the manufacturer recommended that from one to one-and-a-half inches of ice was allowed to accumulate before inflating the deice boots.  It was not reported whether the manufacturer advised this profile during the landing cycle, but icing was determined to not be a contributing factor.

600 pounds of more freight was loaded, above what the first officer requested: Per AAR 88-11 the NTSB gave two scenarios of weight and balance calculations. For simplicity, this article will use the greater calculated CG, though the lesser also exceeded the CG envelope’s aft limits by 8.43 inches.

NTSB report AAR 88/11, page 13, Subsection 1.16.2 Flight 103 Weight and Balance, the flight was launched with 2,283.7 LBS of freight onboard.  The distribution was: 82.5 Nose Cargo; 250 LBS Forward Cabin Baggage; Aft Baggage/Forward Section 1353.0 LBS and Aft Baggage Aft Section 451.0 LBS for a total of 2283.7 LBS of cargo.

NOTE: The Aft Baggage/Forward Section’s structural limits were exceeded by 473 LBS and the total manufacturer’s allowable cargo for the aircraft was exceeded by 373.7 LBS.

AAR 88/11 is vague as to the first officer’s request about weight loaded.  Instead, as per witnesses, e.g. Kodiak’s ramp cargo loadmaster (LM), the first officer (FO) did not understand the difference between weight and volume.  The LM stated that the FO requested the plane be “loaded with 1500 LBS of cargo”.  However, both pilots helped load the aircraft; they should have known how much weight was put onboard.  The LM said the FO told her, “Before we could get the 1500 LBS on board, it would bulk out.”

NOTE: Witness statements are not ‘factual information’; they cannot be used as a Finding nor construed as such in an accident report.  The LM’s statements were Hearsay; no one else could corroborate what was said since both pilots died due to the accident.

Assuming the LM was being truthful (no one alive could refute her), the FO demonstrated poor training.  Furthermore, the LM observed the aircraft’s tail sank low and did not caution the crew.  This is the first cultural issue: the LM suspected the cargo’s weight was excessive and did not alert the crew.

The center of gravity was eight to eleven inches behind the allowable aft limit: The landing limits of flight 103 “was calculated at 184.3 pounds over the maximum allowable landing weight with a CG located 11.20 inches aft of the (aft CG) limit (311.1 inches aft of both takeoff and landing aft limit of 299.9 inches)”.

As the airliner flew the route from Kodiak to Homer, it burned off fuel; result: the CG moved further aft, behind the envelope’s aft limit.  When landing flaps were extended and speed was decreased, the aircraft became unstable.  With the low altitude and throttles set at approach power, the aircraft became uncontrollable, could not recover and crashed.

The flight crew did not comply with Ryan Air and FAA procedures on computing CG: As mentioned, the NTSB came up with two W&B scenarios.  Per AAR 88/11, Ryan W&B procedures required, “The CG will be determined by the flight crew prior to departure of each leg of each flight.  In multi-engine aircraft, it must be recorded on forms provided by the company and held for thirty days at the home base”.  During this time, Ryan crewmembers wrote information on plastic cards with easily erasable grease pencil.  Report AAR 88/11 stated that, per Title 14 CFR Part 135 regulations, duplicate copies of W&B information were not required to be kept by the company.  However, the company policy clearly dictated that duplicates be kept for thirty days.  This is indicative of Ryan’s Operations department not assuring flight crewmembers followed policy, a cultural issue.

Another issue from the investigation was an unorthodox Kodiak ramp practice of ‘memorizing’ weights during hunting season and utilizing informal (unapproved) worksheets instead of writing them on each individual baggage tag in the baggage load calculations.  The cultural issues here are that Ryan Air’s Kodiak ramp came up with some unusual ways of doing business and that the FO had an distorted method of loading an airplane.  The FO, if not the Captain as well, was unfamiliar with some of the flight characteristics of the Beech 1900C, a plane he was charged with carrying passengers on.

The NTSB in 1988 mentioned the preceding four FINDINGS.  The NSTB determined that the LM became confused by the FO’s comment about bulking the cargo bay out.  This finding is absurd; the LM is in a position of responsibility; she should have been certain of her facts.  Furthermore, the lone two recommendations Board Members James Kolstad (Acting Chairman), John Lauber, Joseph Nall, Lemoine Dickinson and Jim Burnett, signed off on were ineffective:

A-88-158: “Expedite the rulemaking project to provide for dynamic testing of seat/restraint systems for airplanes in the commuter category”

A-88-159: “Expedite the publication and dissemination of information on airplane access points … for airplanes with 10 or more seats.”

The recommendations did not address the bizarre practices employed by Ryan’s Kodiak ramp, weight and balance training for the LM and the pilot workforce.  The NTSB did not entertain any truth behind the LM’s statements; indeed, the NTSB did not generate recommendations to ‘fix’ the serious problem at the Kodiak ramp and the entire Ryan Air Operations system.  If one LM is misinformed, then it is a good chance the entire LM group is misinformed.  The same goes for the pilots.

The NTSB report’s omission of important problems in Ryan Air’s W&B program and, thus, the careless exclusion of necessary solutions, e.g. training, as answers to the air carrier’s myriad of problems, unfortunately, did not end with Ryan Air 103.  These investigatory blunders surfaced again in Fine Air 101, ValuJet 592 and Air Midwest 5481, among others; each of these NTSB accident reports could have driven FAA inspectors to expand their surveillance to include other ramp operations that were not mentioned in the accident report and contractors’ training.

The most tragic thing about an accident is the lessons unlearned; when the industry is given an opportunity to prevent future similar events with some common sense and attention to detail, but fail.  Ryan Air Service 103 is just such an accident.

Leave a Reply

Your email address will not be published. Required fields are marked *