NTSB report on the crash of Tanker 11

Air Tanker 45
Air Tanker 45, similar to Tanker 11, on final to drop on the Whoopup Fire near the South Dakota/Wyoming state line in 2011. Photo by Bill Gabbert.

The National Transportation Safety Board probable cause report on the June 3, 2012 crash of Tanker 11 concluded that while preparing to drop retardant on the White Rock fire near the Utah/Nevada state line, the flight crewmembers “did not properly compensate for the wind conditions while maneuvering”. The aircraft impacted the ground before it reached the location for the intended drop, causing the death of pilots Todd Tompkins and Ron Chambless.

A photographer got some pictures of the tanker as it was attempting to make the drop (below). It is likely that the pilots jettisoned the retardant when it became obvious they were too low.

tanker 11 crash
Tanker 11 before the crash. Photo from NTSB.

The P2V, operated by Neptune Aviation, was about to make its second drop on the fire that day. Shortly before the crash it made a dry run over the target area, then when lining up for the drop on the next pass took a different path, which was lower, and made a wider right turn, according to the report.

T11 flight pathThe same day that Tanker 11 crashed, another P2V, Tanker 55 operated by Minden, had a mechanical failure and landed at Minden, Nevada with a main landing gear not fully extended. The aircraft was heavily damaged, but there were no serious injuries. The landing was recorded on video.

In June of this year Tanker 48, another Minden P2V, landed with a collapsed nose gear. Thankfully there were no reported injuries.

We covered the 2012 accidents on Wildfire Today (before Fire Aviation was created).

On June 26, 2010 air tanker 44, a P2V operated by Neptune Aviation also experienced a hydraulic failure upon landing, had no brakes, and went off the runway at Rocky Mountain Metropolitan Airport (JeffCo) in Colorado (map). Both pilots self-evacuated and were walking around when the fire apparatus arrived to put out a fire in one of the engines. Neptune repaired the aircraft and put it back into service.

The NTSB released a nine-page Factual Report on the crash of Tanker 11. Below is the complete text of the one-page probable cause report, released September 24, 2014:

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14 CFR Public Use
Accident occurred Sunday, June 03, 2012 in Modena, UT
Probable Cause Approval Date: 09/24/2014
Aircraft: LOCKHEED P2V-7, registration: N14447
Injuries: 2 Fatal.

NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this public aircraft accident report.

Tanker 11 departed the tanker base to conduct its second fire retardant drop of the day in the same location. Upon arriving in the fire traffic area, Tanker 11 followed the lead airplane into the drop zone, which was located in a shallow valley 0.4 mile wide and 350 feet deep. The lead airplane flew a shallow right turn onto final and then dropped to an altitude of 150 feet above the valley floor while approaching the intended drop zone. While making the right turn onto final behind the lead airplane, Tanker 11’s right wing tip collided with terrain, which resulted in a rapid right yaw and subsequent impact with terrain. The wreckage created a 1,088-foot-long debris field, and a postimpact fire ensued.

Two witnesses took photographs of the accident sequence photos, and an examination of these photographs showed that the lead airplane was positioned ahead of the tanker throughout the flight; however, the orientation of the lead airplane compared to the orientation of Tanker 11 indicated that Tanker 11 did not directly follow the lead airplane’s path to the final drop course. Rather, it was about 700 feet left of the lead airplane’s path and made a wider right turn as it attempted to align with the final drop course. The accident flight crewmembers had previously flown nearly the same exact drop and the lead pilot cautioned them about tailwind conditions during the flight; however, the wider turn suggests that they did not properly compensate for the wind conditions while maneuvering. In addition, the previous flight was conducted at an altitude above the ridgeline. GPS evidence indicates that the accident flight was conducted below the ridgeline, which would have made it more difficult to detect the rising terrain during the wider turn. A review of the airplane’s cockpit voice recorder audio information revealed that the flight crew did not recognize or attempt to correct the reduced clearance between Tanker 11 and the rising terrain until about 2 seconds before impact.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

  • The flight crew’s misjudgment of terrain clearance while maneuvering for an aerial application run, which resulted in controlled flight into terrain. Contributing to the accident was the flight crew’s failure to follow the lead airplane’s track and to effectively compensate for the tailwind condition while maneuvering.

 

2 thoughts on “NTSB report on the crash of Tanker 11”

  1. Just asking.

    How are lead plane pilots trained to allow for larger tanker aircraft maneuvering limitations and to select tracks that provide maneuvering margins for larger aircraft? Are there guidelines, recommendations, and training programs?

    Should USFS publish general abort criterion for tanker aircraft or is common “air sense” enough? In this case was the tankers inability to follow the lead planes flight path a reason for abort?

    Why aren’t tanker aircraft flying with heavy loads and maneuvering with reduced stall margins in gusty wind conditions required to have AOA indicators?

  2. Good question,Bean.

    If USFS has operational control……

    Then they ought to have a curriculum other than NAFA…..

    It ought to be designed on the same level as Flight Safety, Simflite, and others with FAA and NTSB oversight

    Simply putting it on contract operators in a non standard Part 135 etc environment puts the onus on the folks with operational control S the USFS is so kind and generous to remind us.

    Now I think they have a leadplane guide…..but I would highly doubt it meets FAA Part 121, 135, or 141 training standards unless it has been run through the FAA for a cursory look see.

    Just because the FS has all these guides without oversight, doesn’t mean the training is all there.

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