Inadvertent IMC accidents are a problem for helicopter EMS operations. Unfortunately, when the weather is bad sometimes the pressure to accept a flight can rise. The following illustrates what I mean.
According to the NTSB, on the night of Jan. 10, 2003, an air medical helicopter was dispatched from Salt Lake City to Wendover, UT (just more than 100 miles to the west).
After departure, the pilot contacted the Salt Lake City (SLC) air traffic control tower and requested an I-80 transition low-level westbound to Wendover. The tower instructed the pilot to hold east of SLC because of landing traffic. The pilot held at 700 ft agl for about 19 minutes while monitoring the tower and the ATIS frequencies. The pilot stated the weather drastically changed from two-mile visibility to 1/16-mile in fog. Because of the deteriorating weather, the pilot elected to abort the flight and return to the hospital. Returning to the dispatch center, he heard personnel discussing that another air medical service was attempting the flight. The pilot then contacted the other pilot on the radio and reported that he just aborted the same mission because the visibility had reduced to 1/16 miles. The other pilot stated he was going to try to get over the fog.
The other pilot contacted SLC tower for a departure clearance from the hospital. He was cleared to proceed toward SLC. The pilot requested a clearance to 7,000 or 8,000 feet. He was cleared for the ascent and instructed to remain east of SLC. The pilot reported that he attempted to climb; however, he would lose VFR and requested not to do that, but to transition through the SLC airspace to see if it cleared up any better. The tower advised the pilot that the visibility was 1/16-miles and to proceed inbound and remain east of SLC. The tower then asked the pilot if he could continue westbound and the pilot responded, “I’d like to give it a try if I could.”
The tower cleared the flight westbound with instructions to maintain VFR at or below 5,000 feet. A few minutes later the pilot stated he was on the west side of the airfield, and requested to return back to the east. The controller informed the pilot that she could not let him go east until he could see other aircraft on final approach to Runway 34R or she had a break in traffic large enough to get him back to the east side.
While holding, the pilot had the following conversation with his dispatch center:
“We are on the west side of the airport,” the pilot said. “Air Med got sent out for this same damn thing and then they called us to go out. Air Med turned around for low visibility, so they go shopping for another helicopter and we’re turning around at the west side airport. You know, it what’s their determination, you know.”
“I understand,” the dispatcher said. “Unfortunately, that happens all day long. A lot of the dispatch centers do it, but, so I understand that you are turning back 20.”
“I mean, they need help,” the pilot replied.
A few minutes later, the pilot told the tower, “I’m basically inadvertent IMC at this time and declaring an emergency.” Twelve seconds later, the tower asked the pilot whether he had Runway 34L in sight.
“That’s negative and I’m currently on a heading one-five-zero,” the pilot responded.
The tower instructed the pilot to turn right to a heading of 340 degrees for a vector toward SLC. The pilot did not acknowledge the instruction, and the tower controller again attempted to contact him. No further communications were received. The Salt Lake City police department received a 911 call from a witness reporting, “Very thick fog…the helicopter barely missed their trailers…fog is very thick can only see 40 feet ahead.”
The Agusta A109K2 twin-engine helicopter was destroyed when it impacted terrain while attempting to maneuver in dense fog. The instrument rated commercial pilot and the flight paramedic were fatally injured, and the flight nurse was seriously injured.