Date:	Friday 3 July 2020
Time:	11:35
Type:	Cessna 414
Owner/operator:	Sky Ambulance
Registration:	HK-4839
MSN:	414-0492
Year of manufacture:	1974
Fatalities:	Fatalities: 0 / Occupants: 5
Other fatalities:	0
Aircraft damage:	Minor
Category:	Serious incident
Location:	Simón Bolívar International Airport (SMR/SKSM) -   Colombia
Phase:	Landing
Nature:	Ambulance
Departure airport:	Bucaramanga-Palo Negro Airport (BGA/SKBG)
Destination airport:	Santa Marta-Simón Bolívar Airport (SMR/SKSM)
Investigating agency:	Aerocivil
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
A Cessna 41 (RAM series VII conversion) air ambulance suffered a runway excursion and gear collapse.
All five occupants, two pilots and three passengers, were uninjured.

While the crew was configuring the aircraft for landing in Santa Marta, upon lowering the landing gear lever, the green light indicating the left gear was secure did not illuminate. Following the procedure established in the aircraft’s Pilot Operating Handbook (POH), they reconnected the gear verification light, which resulted in the illumination of the light; all three green indicator lights were on.

However, the crew requested permission from the Control Tower for a low-altitude flyby to confirm that the landing gear was extended. The Controller authorized the flyby and informed the crew that the landing gear appeared to be down and locked.

The aircraft touched down normally, but after approximately 170 meters and at a speed of about 60 knots, the crew heard an abnormal noise, and simultaneously, the aircraft veered left of the runway centerline. The crew managed to control the aircraft, but at approximately 20 knots, the left wing and the left engine propeller made contact with the asphalt surface, significantly altering the aircraft's trajectory to the left. The aircraft came to a complete stop between the runway and the left-side safety area (Echo area of the airfield), at coordinates N 11°07’05”, W 74°13’49”.

The crew performed the checklists, secured the aircraft, and directed the evacuation of the passengers. The occupants exited the aircraft on their own without injuries. The aircraft sustained significant damage.

The investigation determined the following probable cause and contributing factors:

Probable Cause
Overload and material aging in the bellcrank assembly 1 with P/N5041001-1 of the left landing gear, which caused an inadvertent retraction of the system during the landing roll.

Contributing Factors
- Aging of the base material used to construct the bellcrank assembly due to periodic operation of the landing gear in various atmospheric and geographical conditions, contributing to physical and intergranular wear of the material.
- Potential improper actions during maintenance practices of “Removal and installation of landing gear” by failing to thoroughly check for clearances and backlash during the installation and adjustment of the landing gear.
- Lack of a service life limitation procedure for this type of component in the Maintenance Manual.
- Inadequate inspection processes in the manufacturer’s manual, as it does not include a deeper non-destructive testing procedure for this type of component to ensure safe and proper operation.
- Inadequate inspection procedures written in the Operator’s General Maintenance Manual to guide maintenance personnel in making appropriate decisions during the installation and adjustment processes for the landing gear, as it is not specified as a special task for the aircraft.
- Although there is a written procedure in Chapter 4, section 4.2, of the General Maintenance Manual for releasing the aircraft after scheduled or unscheduled maintenance, it does not include an effective procedure to ensure the technically controlled operation and functionality of the aircraft system for special cases such as the removal and installation of landing gear.

https://www.elheraldo.co/colombia/avioneta-sufre-accidente-cuando-aterrizaba-en-aeropuerto-de-santa-marta-739474
https://www.webinfomil.com/2020/07/avion-ambulancia-cessna-414-sufrio.html

https://cdn.jetphotos.com/full/6/24064_1518822861.jpg (photo)

ex N446H, PH-MZL, D-ICDD, (D-IMWK), I-CCDD, N7959Q

Gran pericia del piloto permitió que pasajeros de un avión ambulancia resultaran ilesos al aterrizar en Santa Marta pic.twitter.com/rrd9EntR33

— Luchovoltio (@luchovoltios) July 3, 2020

Avión ambulancia Cessna 414 sufrió incidente al aterrizar en el Aeropuerto de Santa Marta https://t.co/nSif6Bx26u

— Webinfomil.com (@Webinfomil) July 3, 2020

Date/time	Contributor	Updates
04-Jul-2020 05:31	gerard57	Added
04-Jul-2020 06:44	RobertMB	Updated [Cn, Location, Departure airport, Destination airport, Source, Narrative, ]
04-Jul-2020 08:28	gerard57	Updated [Damage, Narrative, ]
04-Jul-2020 11:14	Aerossurance	Updated [Embed code, Narrative, ]
04-Jul-2020 11:16	Aerossurance	Updated [Source, Embed code, ]
04-Jul-2020 15:17	RobertMB	Updated [Embed code, Narrative, ]
03-Mar-2021 21:41	rudy	Updated
06-Nov-2024 09:58	ASN	Updated [Other fatalities, Narrative, Accident report, ]