Above: Air Tanker 101, showing the added external tank, December 12, 2017 at Rapid City Airport. Photo by Bill Gabbert.

(Originally published at 8:38 p.m. MDT August 1, 2018; updated at 6:16 a.m. PDT August 2, 2018)

An engine malfunctioned on an air tanker operated by Erickson Aero Air July 30 after taking off from the Coeur d’Alene Airport in Idaho. A person we talked with at the airport said they heard a very loud “boom” as the engine failed, and said the aircraft was an MD-87 air tanker. Mike Ferris, a spokesperson for the U.S. Forest Service, the agency that contracts for the large and very large air tankers used by the federal government, confirmed Wednesday evening that “an Erickson Aero Tanker MD-87 did have an engine upset shortly after takeoff from the Coeur d’Alene Airport on Monday at approx. 1430 PDT”. He said the aircraft landed safely after the incident.

The Coeur d’Alene Post Falls Press reported that unofficial sources have told them that hot debris from an air tanker engine started multiple fires after the pieces fell to the ground north of the airport. They also wrote that the runway was closed while “unspecified debris” was removed. The newspaper was not able to find any government officials who would comment about the cause of the fires, saying it was under investigation.

Kootenai County Government reported on their Facebook page that “several small fires resulted from an aircraft incident” at the airport.

(UPDATE at 6:16 a.m. PDT August 2, 2018: Late yesterday Jim Lyon, Deputy Fire Marshal/Public Information Officer with Northern Lakes Fire District, issued a statement confirming that a jet-powered air tanker under contract to the U.S. Forest Service, at approximately 2:30 p.m. “had mechanical problems on take-off and was able to make an immediate circle route to return to base safely. In so doing, it appears the plane was discharging some sort of material as a result of the mechanical problem, starting several fires throughout the area approximately a five mile radius of the airport.” Marshal Lyon said “up to eight fires” started by the incident were under control by the evening of July 30th.)

Below is an excerpt from a July 31 article in the Spokesman Review about the incident:

Jim Lyons, spokesman for Northern Lakes Fire District, said crews battled about seven fires, though none grew to the size of a major wildfire. The first blazes started about 2 p.m. and spread from there. Shoshana Cooper, spokeswoman for the U.S. Forest Service in North Idaho, said the fires burned to the northwest, south and east of the airport near U.S. Highway 95. She said they burned mostly grass and brush and were not affecting structures. As of 3:30 p.m., no structures had been lost. Multiple aircraft were sent in to drop retardant on the blazes, but firefighters weren’t sure early Monday afternoon how large the fires had grown.

KXLY reported that a firefighter was injured while working on one of the fires near the airport:

A Kootenai County Fire and Rescue firefighter was injured Monday evening when he was struck by a vehicle that was backing up on Dodd Road by Strayhorn while responding to fires burning near the Coeur d’Alene Airport. He was evaluated at the scene. His injuries were not life threatening, but he was transported to Kootenai Health as a precaution.

The airport resumed normal operation at about 6:30 p.m. Monday.

We were not able to find a SAFECOM report about the incident, and very few people are willing to talk about it. Our calls to personnel at Erickson Aero Air late in the afternoon August 1 either were not returned right away or the employees we talked with were not able to comment.

This is not the first time that an engine on an Erickson Aero Tanker MD-87 exploded and falling debris caused problems after hitting the ground. On September 13, 2015 debris from a failed engine landed in a residential area of Fresno, California. One chunk of metal crashed through the rear window of a car, while other shrapnel was found in city streets.

See huge hole in back window? A piece of air tanker dropped onto woman’s car off Barton & Swift. @FresnoPolice here. pic.twitter.com/x20xt2M9Ok — Connie Tran (@MissConnieTran) September 13, 2015

There has been concern about retardant being ingested into the engines when the MD-87 is making a drop, since at least 2014. A SAFECOM filed back then considered the possibility after engine surges or intermittent power was a problem for one aircraft after making a drop. Photos were taken of retardant stains on the fuselage caused by retardant flowing over the wing.

The first fix that Erickson Aero Air implemented was in 2014, “a new spade profile that has proved to eliminate this problem by keeping the fluid column much more vertical”.

Then in June, 2017 the company took a much more radical step. They had an external tank, or pod, fabricated and installed below the retardant tank doors, which lowered the release point by 46 inches, mitigating the problem, Kevin McLoughlin, the Director of Air Tanker Operations, said at the time.



On December 12, 2017 I was given a tour of Tanker 101 by the flight crew while it was in Rapid City, and noticed there was evidence of retardant flowing over the top of the wing. If you check out the profile photo of Tanker 101 at the top of this article, you will see that the top of the wing is not much lower than the height of the engine intake.

Another unique characteristic of the MD-87 is that they are required by the FAA to lower the gear while dropping — in fact it is specified in their Supplemental Type Certificate (STC) issued by the FAA. That 10-page STC uses the words “stall” or “stalling” 60 times, an average of 10 times on every page.

Our view

How many second chances should an air tanker design get after exploding engines on two occasions drop hot shrapnel over a city and at an airport? The FAA and the Interagency Airtanker Board should rescind the Supplemental Type Certificate and the IAB approval and carding of the air tanker before something much worse happens than a car is damaged while parked at a home, shrapnel closes a runway, multiple wildfires are ignited, and a firefighter is injured putting out the blaze. I fear not only for the safety of the flight crews in the MD-87’s, but people on the ground who have every right to expect that firefighting air tankers on U.S. Forest Service contracts will not kill or injure them with exploding engines. And, that an air tanker hired to suppress fires will not start them.

Thanks and a tip of the hat go out to Tom.

Typos or errors, report them HERE.

Typos, let us know HERE. And, please keep in mind our commenting ground rules before you post a comment.

Share this... Reddit