Grid testing for the 737

Coulson Aviation intends for the 737 to be able to haul 4,000 gallons of retardant, or passengers

Above: Air tanker 137, a 737-300, at the grid test near Lancaster, California, September 3, 2018. Coulson photo.

Coulson Aviation posted these photos September 3, 2018 of one of their recently converted 737-300’s, Tanker 137, as it was undergoing grid testing in Lancaster, California.

The process involves dropping retardant over a grid of thousands of cups intended to measure the volume and consistency of the pattern when it hits the ground. The Interagency AirTanker Board requires passing this and other certifications before an aircraft can be “carded” as a federal air tanker, which makes it eligible for a contract to fight fires.

Some air tankers are required to make 20 to 25 drops over several days at the test. Firefighting hand crews are usually hired or borrowed to retrieve the cups after each drop. It is a very expensive process. The last time we checked the price of retardant was $2.50 to $3.00 a gallon, depending on which air tanker base it is delivered to.

737 air tanker T-137 grid test retardant
Air tanker 137, a 737-300, at the grid test near Lancaster, California, September 3, 2018. Coulson photo.
737 air tanker T-137 grid test retardant
Air tanker 137, a 737-300, at the grid test near Lancaster, California, September 3, 2018. Coulson photo.

The interior of Coulson’s 737 looks futuristic.

737 air tanker T-137
Coulson’s installation of the internal retardant tank in the passenger compartment of their 737-300. They intend for the aircraft to have seats available for passengers, enabling it to do double-duty; drop retardant or haul passengers. Coulson photo.

They intend for it to be able to haul 4,000 gallons of retardant, or passengers. Last year Britt Coulson said, “With a full retardant load and 4.5 hours of fuel we are so far under max gross weight we are going to leave the full interior and galleys in even when just in airtanker mode.”

The company purchased six 737-300’s from Southwest Airlines.

Art Prints

The first drops from the 737 air tanker

Above: One of the first test drops by a 737 air tanker, Coulson’s T-137. Photo by Jeremy Ulloa.

On July 13 the 737 that Coulson Aviation has been converting into an air tanker made its first drops. In this case it was a series of water drops by Tanker 137 while flying out of San Bernardino, California.

Britt Coulson said, “The 4,000 USG RADS-XXL/2 performed perfectly as did the airplane. Our flight crew couldn’t have been happier with the handling characteristics and our split tank worked as designed with no CG shift during the drop.”

Next week they will finish flight testing with the FAA, and will soon begin static tests of the tank system. They are working with the Forest Service to schedule the grid test.

Mr. Coulson expects Tanker 137 will be ready to fight fire in August.

air tanker 137 737 fire
T-137. Photo by Jeremy Ulloa.
air tanker 137 737 fire
One of the first test drops by a 737 air tanker, Coulson’s T-137. Photo by Britt Coulson..

737 air tanker undergoing FAA testing

(Originally published at 3:47 p.m. MDT June 17, 2018)

One of Coulson’s recently converted 737’s, Tanker 137, is in San Bernardino for certification testing by the FAA.

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(UPDATED at 1:38 p.m. MDT June 21, 2018)

Coulson may have seen Donn’s question about the loading ports. Here is what they posted on Facebook June 20:

Photos of DC-10 air tankers at McClellan

And, a 737 air tanker

Above: T-911, a DC-10, at McClellan October 13, 2017, by Sergio Maraschin.

Sergio Maraschin sent us these photos that he took of DC-10 air tankers at Sacramento McClellan Airport in 2017.

DC-10 air tanker
T-910 at McClellan October 10, 2017, by Sergio Maraschin
DC-10 air tanker
T-910 at McClellan July 30, 2017, by Sergio Maraschin

Thanks Sergio!

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UPDATED at 11:40 MT February 16, 2018. 

A person who prefers that we not disclose their name sent us this photo of one of Coulson’s freshly painted 737 air tankers at McClellan.

Air Tanker 138 737
Coulson’s Air Tanker 138, a 737, at McClellan, January 30, 2018.

Articles on Fire Aviation tagged 737.

A second 737 air tanker emerges from paint shop

Coulson’s Air Tanker 138 makes its debut

Air Tanker 138, the second of Coulson’s six recently acquired 737-300’s to emerge from the paint shop, is sporting the same livery as Air Tanker 137 that was introduced to the public in May.

Britt Coulson said the conversion of T-137 is almost complete. When it’s done in early February, T-138 will be inducted into the modification process.

The conversion of the company’s fourth C-130, T-134, is nearly done, Mr. Coulson said.

Air Tanker 138 Coulson
Air Tanker 138. Photos by Coulson.

Firefighting aircraft on Twitter

Isaac notified us about these videos and photos. Thanks Isaac!

Photos of Coulson’s 737-300 air tanker

The company expects to have the conversion complete by the end of this year.

On May 21 we told you about Coulson Aviation branching out into a new line of air tankers to add to their three C-130s and a fourth C-130 that is being converted now. The company has purchased six 737-300’s from Southwest Airlines and intends to convert at least some of them into air tankers.

The first conversion has started, with a freshly painted 737 rolling out of the paint shop in Spokane today.

The next step is to add a gravity-based tank which will have the same technology used on their C-130’s.

Coulson 737 air tanker

The air tanker is being designed as a multi-use aircraft with the ability to haul passengers. Britt Coulson said, “With a full retardant load and 4.5 hours of fuel we are so far under max gross weight we are going to leave the full interior and galleys in even when just in airtanker mode.”

Coulson 737 air tanker

 

The photos were provided by Coulson Aviation.

Coulson to convert 737’s into air tankers

Coulson Aviation is adding not only additional air tankers to their fleet, but is branching out into a different model of aircraft. The company has purchased six 737-300’s and intends to convert them into 4,000-gallon “Fireliner” air tankers. Britt Coulson said they saw an opportunity when Southwest Airlines made a decision to replace their 737-300’s with the new 737-Max. Since the FAA only allows Southwest pilots to fly two of the 737’s with the same rating, the airline opted to sell the 737-300’s even though they have a relatively low number of hours in the sky.

The first conversion has started, with a freshly painted 737 scheduled to roll out of the paint shop in Spokane on May 22, 2017. The next step is to add the gravity-based tanks which will have the same technology used on their C-130’s.

The air tanker is being designed as a multi-use aircraft with the ability to haul passengers. Mr. Coulson said, “With a full retardant load and 4.5 hours of fuel we are so far under max gross weight we are going to leave the full interior and galleys in even when just in airtanker mode.”

The company likes the three C-130’s that they have already converted to air tankers, but finding additional C-130’s for the civilian market is very difficult.

A 737 will be able to use some air tanker bases that larger aircraft, like the C-130, can’t, with a wingspan that is about 38 feet shorter.

Mr. Coulson said they expect to begin installing the retardant system in June with a completion date of December of this year. When that is complete they will start on another. The first conversion will be done by Coulson Aircrane Canada.

More photos of the aircraft.