| Occurrence Briefs are concise reports that detail the facts surrounding a transport safety occurrence, as received in the initial notification and any follow-up enquiries. They provide an opportunity to share safety messages in the absence of an investigation. |
What happened
On 12 September 2018, the crew of a Beech Aircraft Corp 76 departed Jandakot, Western Australia to conduct a flight test with two crew members on board.
Just after take-off, the crew proceeded 28 km south of Jandakot, WA, operating under Visual Flight Rules[1] (VFR). Whilst in the local training area, the crew conducted some training manoeuvres, which also included three in-flight gear extensions. The first two gear extensions were performed without incident. During the third gear extension, the nose gear failed to extend and lock into place. The crew attempted to extend the gear using the emergency procedures checklist located in the aircraft’s flight manual. After completing the landing gear manual extension checklist (Figure 1), the crew were unable to extend the nose gear. This was confirmed by the nose gear light not being illuminated and by visual inspection in the form of a mirror located on the inside of the left engine cowling. The crew conducted a return to Jandakot, declared a PAN-PAN[2] call to Jandakot tower and instructed the Tower that they would be performing a nose gear up landing.
Air Traffic Control (ATC) acknowledged the PAN-PAN and instructed the crew to hold south of the airport to process all arriving traffic in anticipation that the runway would become unserviceable, and to give the crew time to attempt to extend the gear and prepare for their approach. The crew conducted a fly-by of the tower for a visual inspection of the landing gear. ATC confirmed that the nose gear was not extended. Emergency services and procedures were activated and the aircraft was holding in the circuit area
As the aircraft approached for landing, the crew completed the gear up landing checklist (Figure 2), which instructs them of the proper configuration the aircraft needs to be in to perform a gear up landing to minimise injury and damage to the aircraft. Prior to touching down on the runway, at about 200 ft above ground level, the crew pulled the engine throttles back to idle, the engine fuel mixtures to idle cut-off, the propeller pitch controls to feather and all electrical systems were turned off to prevent any damage to the engines, propellers and also to reduce the risk of a fire. As the main landing gear wheels touched down on the runway, the crew kept backpressure on the control column to keep the nose of the aircraft off the ground as long as possible and to slow the aircraft down. As the aircraft’s speed started to slow down, the nose slowly started to drop onto the runway and came in contact with the runway surface. The aircraft came to a complete stop shortly after. The crew disembarked the aircraft unharmed. The aircraft sustained minor damage to the nose section.
Engineering inspection
Following the incident, the inspection of the nose gear section revealed that the landing gear pivot bolts and leg pins on the landing gear doors were worn, which caused it to malfunction and prevented the doors from opening, therefore not allowing the nose gear to extend.
Figure 1: Landing gear manual extension checklist
Figure 2: Gear up landing checklist
Safety message
Unanticipated failures can occur during flight. In this incident, although the aircraft was within the necessary distance from the runway to complete a nose gear up landing, it is safer to wait until the main landing gear has touched down on the runway before shutting down and feathering the engines. This is to ensure that if the aircraft has to go around or take-off again due to safety reasons or obstructions on the runway, the aircraft will have the necessary engine performance it requires to perform this task.
The crew, in this instance, took all possible precautions by following non-normal procedures, conducting additional checks to assess the situation, providing clear communications to ATC and returning the aircraft to land.
About this report
Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.
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- Visual Flight Rules (VFR) - are a set of regulations under which a pilot operates an aircraft in weather conditions generally clear enough to allow the pilot to see where the aircraft is going. Specifically, the weather must be better than basic VFR weather minima.
- PAN-PAN - The radiotelephony message PAN-PAN is the international standard urgency signal that the crew on board an aircraft uses to declare that they have a situation that is urgent but, for the time being at least, does not pose an immediate danger to anyone's life or the aircraft itself.