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:

****

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.

 

NTSB report on Tanker 48’s collapsed nose gear

Tanker 48 at Fresno
Tanker 48 lands on collapsed nose gear at Fresno.

The National Transportation Safety Board has released preliminary information about the June 15 accident in which Minden’s Tanker 48, a P2V, experienced a hydraulic failure, resulting in the nose gear collapsing while it landed at Fresno, California.

****

“NTSB Identification: WPR14TA248
14 CFR Public Use
Accident occurred Sunday, June 15, 2014 in Fresno, CA
Aircraft: LOCKHEED SP 2H, registration: N4692A
Injuries: 2 Uninjured.

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this public aircraft accident report.

On June 15, 2014, about 2044 Pacific daylight time, a Lockheed SP-2H, N4692A, was substantially damaged when the nose wheel landing gear collapsed during landing roll at the Fresno Yosemite International Airport (FAT), Fresno, California. The airplane was registered to Minden Air Corporation, Minden, Nevada, and operated as Tanker 48 by the United States Department of Agriculture (USDA), Forestry Service, as a public use flight. The airline transport pilot (ATP) rated captain and the ATP rated first officer were not injured. Visual meteorological conditions prevailed and a company flight plan was filed for the local fire fighting flight. The flight originated from Porterville Municipal Airport (PTV), Porterville, California, at 1934.

The captain reported that following an uneventful aerial drop, the flight was returning to PTV. During the descent check, he noticed that the hydraulic pressure indicated 0 and that the first officer subsequently verified that the sight gauge for the main hydraulic fluid reservoir was empty. The first officer opened the jet engine doors successfully as the captain selected gear down with no response. The captain notified base personnel at PTV of the situation and informed them that they would be orbiting to the east of the airport to troubleshoot. The captain and first officer performed the emergency checklist, and extended the nose wheel landing gear successfully. The captain stated that the first officer then installed the pin to the nose wheel landing gear as part of the emergency checklist.

The flight diverted to FAT due to a longer runway and emergency resources as both pilots briefed the no-flap landing procedure, airspeeds, and approach profile. As the flight continued toward FAT, the flight crew informed Fresno Approach Control of the hydraulic system failure and continued to perform the emergency gear extension checklist. The first officer extended the main landing gear using the emergency gear release, which resulted in three down and locked landing gear indications in the cockpit. As the flight neared FAT, the first officer added two gallons of hydraulic fluid to the main hydraulic reservoir while the captain attempted to extend the flaps unsuccessfully. Subsequently, the flight landed on runway 26R. During the landing roll, the nose wheel landing gear collapsed and the airplane came to rest nose low.

Examination of the airplane by representatives from the Forest Service revealed that the forward portion of the fuselage was structurally damaged. The airplane was recovered to a secure location for further examination.”

****

Below is photo of Tanker 48 after landing on all three wheels at Rapid City, July 21, 2012, while working the Myrtle Fire.

Tanker 48 at Rapid City. Photo by Bill Gabbert.
Tanker 48 at Rapid City. Photo by Bill Gabbert.

Tanker 48 lands on collapsed nose gear at Fresno

Tanker 48 at Fresno
Tanker 48 lands on collapsed nose gear at Fresno.

Minden’s Tanker 48 experienced a hydraulic problem while working the Shirley Fire in California and diverted to Fresno, California where upon landing, the nose gear collapsed. Thankfully there were no injuries. Mike Ferris, a spokesperson for the U.S. Forest Service, described it as “a minor mishap”.

More details are at Wildfire Today, along with a history of similar air tanker accidents.

Two air tankers still on active duty

Tanker 48 at Rapid City Air Tanker Base, July 21
Tanker 48 at Rapid City Air Tanker Base, July 21. Photo by Bill Gabbert

(Revised at 7:37 a.m. MT, December 4, 2012)

The mandatory availability periods for the nine large air tankers on national contracts ended in August, September, and October, but two P2Vs are still working today due the warm, dry weather that some areas of the country are experiencing. Tanker 48, operated by Minden, and Neptune’s Tanker 43 are the two that are working on a day by day basis through “optional use” provisions in their contracts, according to Jennifer Jones, a spokesperson for the U.S. Forest Service in Boise.

Air tankers were requested early Saturday morning, December 1, for the rapidly spreading Fern Lake Fire that was moving toward structures west of Estes Park, Colorado. Fire managers were told that the only large air tankers sill working were in California but were unavailable due to weather in the Bay Area, according to David Eaker, a spokesperson for the Fern Lake Fire.

Today two large air tankers were supposed to be parked on the ramp at JEFFCO air tanker base northwest of Denver after being ferried in from California, but only one made it, Tanker 48. The other one, Tanker 43 had to stop in Durango, Colorado, unable to climb over the continental divide due to weather. We’re thinking the old P2V does not have de-icing equipment.

If the USFS is going to keep air tankers working into the winter, maybe a better choice of which ones to keep on would be a couple of the BAe-146s, which I assume have de-icing equipment.

The one tanker at JEFFCO, 48, has not been used on the Fern Lake Fire yet due to strong winds over the fire. Mr. Eaker told Wildfire Today that they may be used very soon to pretreat some areas where large burnouts are planned, thanks to improving weather forecasts indicating decreasing winds.

Tanker 43 was responsible for closing the Rapid City Airport for 40 minutes on June 20 when an engine failure on takeoff resulted in the crew jettisoning the 2,000-gallon load of retardant on two runways and a taxiway.

Tanker 43 landing at Rapid City Air Tanker Base
Tanker 43 landing at Rapid City Air Tanker Base, July 21, 2012. Photo by Bill Gabbert

 

(This article was edited to reflect the fact that one of the air tankers was delayed ferrying to JEFFCO. Thanks Rob.)