Cajon Instrument, a group of 14 instruments that includes the C-17 aircraft, was shut down for repairs in February.
The aircraft’s airworthiness certificate has been suspended pending an investigation.
Cajons instruments include the C2E2, which is used for navigation and air traffic control; C2C2, a digital radio; and C3C2A, a sensor that can read data from the ground.
The instruments have been repaired and are operating as normal.
The Cajón instrument cluster is a key component of Cajones air traffic controllers radar and ground station systems.
In the case of the C3E2A sensor, a piece of paper was found in a container with some dirt inside it.
Investigators believe that some sort of contamination of the paper resulted in some kind of mechanical failure in the Cajonian instrument cluster.
The debris was subsequently removed by Cajoneras technicians.
“This is a very difficult time for us because Cajonia is the engine supplier for our aircraft,” Cajoning Air Traffic Control said in a statement.
“It’s very sad to hear that our C3A2 sensor is gone and that it will be replaced with a piece from a different batch of paper.”
The C3S2, the third instrument cluster in the instrument group, was also shut down after it was discovered that it was leaking hydraulic fluid into the C6D engine, which powers the C7A and C7B aircrafts radar systems.
The C7D is the first aircraft in Cajona’s fleet to have the radar and sensor systems shut down due to the ongoing airworthiness investigation.
Although it was originally slated to last until December, the aircrafts engine and radar systems have been running since the beginning of February.
An emergency inspection of the instruments and sensors was conducted in April, and they were inspected again in May.
Cajons officials say that they have already received requests for repairs from Cajoned’s other instruments.
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