A corporate jet flight crew reported SNS ATC issued a low altitude alert when their aircraft turned the wrong direction on the SNS Chalone3 Departure SID even though the FMS was correctly programmed.
Synopsis
A corporate jet flight crew reported SNS ATC issued a low altitude alert when their aircraft turned the wrong direction on the SNS Chalone3 Departure SID even though the FMS was correctly programmed.
Narrative
Flight crew taxied to Runway 13 for departure. Upon reaching the hold short point control tower queried the crew if we were familiar with the SID CHLN3.SNS. It caused the crew to take a closer look. I replied to the tower that we had briefed it but had not flown it. We also had the plate pulled up on our Flight Bag. We re-briefed the departure and verified that we had it programmed properly in our FMS. Tower cleared us for departure to 6000 feet and immediately called traffic to us at 12 o'clock and in the same breath said contact departure. Departure immediately called traffic 11 o'clock 5500 and traffic 2 o'clock 6000. I was looking for traffic and Captain elected to engage the autopilot to assist in traffic avoidance. The aircraft began a right turn which brought us into an airspace with a higher MSA. At that point departure gave us a low altitude alert and a heading to fly; but by that time the aircraft was already intercepting the 114° radial to SARDO. The rest of the flight was conducted in a normal manner. Upon debriefing with the Captain we both agreed that had we not been launched into an opposing traffic situation we would have caught the mistake of the FMS.
Second reporter narrative
We were departing SNS airport. We were given a clearance to depart runway 13; for the Chalone Three Departure and a level off altitude of 6000 feet. My co-pilot and I briefed the departure; and programmed it in the FMS. We were given taxi instructions to runway 13. While holding short; SNS control tower asked us if we were familiar with the Chalone Three departure. We informed him we had the departure plate up in the airplane; it had been briefed; and we reverified it was correct in the FMS. We were given take off clearance. After liftoff tower advised us of VFR traffic; opposite direction; 11 o'clock at 5500 feet; then we were handed off to departure. We got the after takeoff flows completed. My copilot was looking for traffic which was rapidly approaching. I initially started a left turn when Departure advised us of an additional VFR traffic at 2 o'clock and 6000 feet. We verified that nav mode was selected and engaged the auto pilot to look for the traffic. During this time; even while the FMS was loaded and verified to be correct by both myself and copilot; it initiated a right turn; to which ; being extremely busy looking for 2 VFR targets at the altitudes we were going to; I thought it was intercepting the correct course to go to the first fix on the departure. This caused us to be right of the course depicted on the Departure procedure. We identified the opposing traffic; and at that time the aircraft began a left turn towards Sardo; the first depicted point per the departure procedure. Being right of course caused us to fly over a higher MSA area. However; we were VMC; and never felt any danger of terrain. Looking outside for traffic and keeping terrain in sight as well we never had any EGPWS warning etc about terrain in the cockpit. Departure then gave us a heading of 060 and told us a phone number to copy down. Being busy due to looking for 2 conflicting targets we thought the FMS and auto pilot were flying the correct course while it in fact was not even though it was programmed correctly and verified. Upon landing safe back in Chandler and contacting NORCAL on the number provided I was informed there were several issues with that departure recently leading to many pilot deviations. Had we not have been given take off clearance into opposing traffic I believe we would have had a better chance of catching the fact the FMS was taking us right of course. Also; the fact SNS tower asked us if we were familiar with the departure; and now knowing there have been multiple pilot deviations on that departure; I feel something may need to be done; possibly a note depicting to fly the departure on raw data; or if the tower is going to ask pilots if they are familiar with the departure; explain what previous incidents have occurred.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.