Incident Name: Bus Fire
Personnel: 2 lives lost
Agency/Organization: San Joaquin Helicopters, a Delano, CA-based company under contract with CDF (now CAL FIRE)
Position: both pilots, aerial firefighters
Lawrence L Groff, Pilot, 46 years, Tanker 87
Lars B Stratte, Pilot, 55 years, Tanker 92
Eight airtankers and three helicopters were working a 270-acre wildland fire south of Ukiah, California. The fire began near a suspected methampetamine lab. Airtanker Pilots Groff and Stratte were operating air tankers carrying 800 gallons of fire retardant each. The two aircraft collided above the fire as one prepared to make a drop while the second was joining the rotation orbit of ready aircraft. Both pilots were killed and both aircraft were completely destroyed. Two men were charged with arson, murder, and drug production charges in relation to the origin of the fire.
This accident started the idea of the FTA -- Fire Traffic Area (pdf)-- as we know it today. Sue Gethen
Larry Groff Lars Stratte
Accident Location: primary wreckage for Tanker 92
Accident Location: primary wreckage for Tanker 87
- Concise Information from the NTSB, FAA, USFS, CDF (CALFIRE), AAP and WLF Staff:
- Aug 27, 2001 - Tanker 92 & Tanker 87
- 2 killed: Lars Stratte, 46 years, Larry Groff, 55 years
- Operator: CDF (now CAL FIRE)
- Type: Grumman TS-2A (or S-2T)
- midair collision near Hopland CA, Bus Fire, McNab Ranch
- T-92 FAA Registration # N442DF; NTSB #LAX01GA291A
- T-87 FAA Registration # N450DF; NTSB #LAX01GA291B
- National Transportation Safety Board: Probable Cause T-92 (html) | Probable Cause T-87 (html) | Probable Cause T-92 (223 K pdf) | Probable Cause T-87 (223 K pdf)
During an aerial fire suppression mission for the California Department of Forestry (CDF), two Grumman TS-2A airplanes, operating as Tanker 92 (N442DF) and Tanker 87 (N450DF), collided in flight while in a holding pattern awaiting a retardant drop assignment on the fire. All of the airplanes fighting the fire were TS-2A's, painted in identical paint schemes. The Air Tactical Group Supervisor (AirTac) was orbiting clockwise 1,000 feet above the tankers, who were in a counterclockwise orbit at 3,000 feet mean sea level (msl). The pilots of both aircraft involved in the collision had previously made several drops on the fire. Records from the Air Tac show that Tankers 86, 91, and 92 were in orbit, and investigation found that Tanker 87 was inbound to enter the orbit after reloading at a nearby airport base. AirTac would write down the tanker numbers as they made their 3-minutes-out call, and usually ordered their drops in the same order as their check-in. The AirTac's log recorded the sequence 86, 91, 21, and 92. The log did not contain an entry for Tanker 87. Other pilots on frequency did not recall hearing Tanker 87 check in. Based on clock codes with 12-o'clock being north, the tankers were in the following approximate positions of the orbit when the collision occurred. Tanker 92 was at the 2-o'clock position; Tanker 86 was turning in at the 5-o'clock position; and Tanker 91 was in the 7-o'clock position. The AirTac's log indicated that Tanker 92 was going to move up in sequence and follow Tanker 86 in order to drop immediately after him. Post accident examination determined that Tanker 92's flaps were down, indicating that the pilot had configured the airplane for a drop. Tanker 92 swung out of the orbit wide (in an area where ground witnesses had not seen tankers all day) to move behind Tanker 86, and the pilot would likely have been focusing on Tanker 86 out of his left side window. Tanker 87 was on line direct to the center of the fire on a path that witnesses had not observed tankers use that day. Reconstruction of the positions of the airplanes disclosed that Tankers 86 and 91 would have been directly in front of Tanker 87, and Tanker 92 would have been wide to his left. Ground witnesses said that Tanker 87 had cleared a ridgeline just prior to the collision, and this ridgeline could have masked both collision aircraft from the visual perspective of the respective pilots. The right propeller, engine, and cockpit of Tanker 92 contacted and separated the empennage of Tanker 87. The propeller chop was about 47 degrees counterclockwise to the longitudinal axis of Tanker 87 as viewed from the top. The collision appeared to have occurred about 2,500 feet, which was below orbit altitude. CDF had no standard operating manual, no established reporting or entry point for the holding orbits, and a tanker could enter any point of the orbit from any direction. While no standardized procedures were encoded in an operating manual, a CDF training syllabus noted that a tanker was not to enter an orbit until establishing positive radio contact with the AirTac. The entering tanker would approach 1,000 feet below AirTac's altitude and stay in a left orbit that was similar to a salad bowl, high and wide enough to see and clear all other tankers until locating the tanker that it was to follow, then adjust speed and altitude to fall in behind the preceding airplane.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows: the failure of both pilots to maintain an adequate visual lookout. The failure of the pilot in Tanker 87 to comply with suggested procedures regarding positive radio contact and orbit entry was a factor.
- National Transportation Safety Board: Full Narrative (html)
- National Transportation Safety Board: Factual Report T-92 (100 K pdf) Factual Report T-87 (100 K pdf)
- For more information consult the NTSB on-line lookup utility Use NTSB Accident Numbers LAX01GA291A (Tanker 92) and LAX01GA291B (Tanker 87). The reports are written identically except for tail numbers. The report includes both aircraft.
- Report on Interpretation of Post-Mortem Alcohol in Autopsy (205 K pdf)
- USFA Memorial Database: Lawrence L Groff | Lars B Stratte
- They Said It starting on 8/27/01 and continuing through Northern Michael's comment about PSOB and to the end of the month
- They Said It Dec 13, 2001 Achieving State PSOB for families of fallen AT Pilots
- Suspect Arraigned In CDF Plane Crash Case; Two Pilots Killed Fighting Blaze In Mendocino County
August 29, 2001 | Online Article
HOPLAND, Calif. -- The man accused of starting a campfire that led to the deaths of two air tanker pilots in Mendocino County was arraigned Wednesday on murder charges. Frank Brady is charged with two counts of murder. Brady, 50, of Redwood Valley, was booked Tuesday and is being held without bail.
Two California Department of Forestry pilots died Tuesday fighting the blaze near Hopland when their tankers clipped wings and crashed.
Larry Groff of Santa Rosa and Lars Stratte of Chico were identified as the pilots killed.
- The History of Aerial Firefighting Planes in California
- Communique' Summer/Fall 2001 California Department of Forestry and Fire Protection (now CAL FIRE) (1,350 K pdf)
The loss of our own (on page 3 with remembrances and condolences on page 4)
When two CDF S-2A airtankers collided while working a fire in Mendocino County on August 27, 2001, CDF lost two members of its family, and two families lost their husbands, fathers, brothers, and friends. From family and fellow tanker pilots, it is clear that Larry Groff of Windsor, California, and Lars Stratte of Redding, California, died doing a job they loved, but that doesn’t make the loss any easier.
Larry, a Navy pilot for 20 years, began flying CDF S-2’s in 1997. He flew out of the Sonoma Air Attack Base in Santa Rosa. Lars was an air attack pilot for the US Forest Service before he began flying S-2’s in 1999. He flew out of the Chico Air Attack Base.
Both pilots were employees of San Joaquin Helicopters, Inc. the contractor that has provided CDF with airtanker pilots, and airtanker and helicopter maintenance since January 1996.
Memorial services for both pilots were testaments to the closeness of members of the emergency services family - a sea of dress uniforms amidst family and friends.
Services for Larry Groff began as a simple pine casket, draped by an American flag in the back of a vintage fire engine led a procession of 150 emergency vehicles to the Charles M. Schultz Airport in Sonoma County. There, mourners heard friends and family talk about a “humble, unassuming” man who loved to fly. CDF Pilot Jimmy Barnes told the crowd that “Larry thought of himself as a simple country boy…. but he was so much more than that.”
Larry is survived by his wife, Christine; daughters Kim, Kara, Kristen, and Susie; and son Mick.
Over 2000 attended Lars Stratte’s memorial service at Bethel Church in Redding. His son, Ian, spoke about the job his dad helped him get refueling tankers this fire season at the Redding Municipal Airport. He said that his dad died doing something he loved, and that “he was the kind of man that I want to be in so many ways.” Lars is survived by his wife, Terri Ann; sons Ian and Tryg; brothers Tryg, Joel Stratte-McClure; sisters Leslie Curfman and Scott Peters; and mother Helen.
In memory of the two fallen pilots, CDF Director Tuttle retired their respective airtanker numbers 87 and 92.
The Mendocino County Sheriff’s Office arrested two men in connection with the cause of the fire that Lars and Larry died battling. The Bus Fire was contained at less than 250 acres.
Photos of Larry Groff Memorial Service:
Monument near Hopland/Ukiah
- FIRE BOMBERS: The Stratte-Groff Memorial page
- By Joel Stratte-McClure Memorial page to Larry and Lars
- California Memorial Firefighter Wall in Sacramento: California Memorial LODDs by Wall Order. (84 K pdf) --see page 22
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