Republished from Verical Mag

BHI² (Squared) Helicopters is working towards certification of a modular slide-in firefighting tank suitable for Black Hawk helicopters that are configured with a normal cargo door.

The 925-gallon tank can be installed in Black Hawk helicopters without cutting or modifying the aircraft; the existing tie-down points on the Black Hawk are used to secure the tank in the aircraft.

The company brought its H-60X research and development aircraft, equipped with the new firefighting tank, to the static display at this year’s HAI Heli-Expo 2019 in Atlanta, Georgia. Rob Reyno Photo

“Most tanks use a hydraulic system that controls the door system,” said Bart Brainerd, vice president at Brainerd Helicopters. “This is an electric drive system, so it uses a 48-volt electric motor with a gearbox that drives the doors. It provides coverage levels [and] selectability; it provides partial tank drops, [and it] uses an electric snorkel.”

The 15-foot snorkel can pull up 925 gallons of water in roughly 50 seconds when only the pump loader is under the water. In instances where there are deeper water sources and the snorkel can be further submerged into the water, the tank can be filled in about 40 seconds.

The firefighting tank was initially set up to drop water from the left side of the aircraft, but Bart Brainerd said “as we revise the tank going forward, it will actually be able to [drop water] in an even current or the right side of the aircraft going forward.”

BHI²’s tank will come with a software package that will allow pilots to perform different types of drops including split drops, half-tank drops, and third-of-a-tank drops.

The company is about 60 days out from receiving a supplemental type certificate (STC) on the tank system, Bart Brainerd told Vertical. “We’re excited to see this go into operation fighting fire hopefully this summer,” he added.

The modular slide-in tank has a 925-gallon capacity and can be installed in Black Hawk helicopters without cutting or modifying the aircraft. The tank uses an electric drive system and features an electric snorkel. Rob Reyno Photo

Flight tests with the tank installed on BHI²’s research and development aircraft (H-60X) began in September 2017, and it was tested through the spring of 2018. The tank has been successfully tested at the aircraft’s Vne of 193 knots. The company is estimating the tank will be flown at a speed of 160 knots once certified, but potentially as high as 175 knots — which is the same speed BHI²’s bubble window is certified at.

BHI² has also tested the hover drop capability of the tank at 200 feet, “and it has very good penetration,” Bart Brainerd said. “That was a very important part of our design — head pressure — so we wanted to keep something that was about in the neighborhood of what the bucket can do.”

The tank has also proven to be versatile with different modes of operation. “One of the features that we’re very proud of with this tank is that we can drop water with the tank and in 10 minutes we can reconfigure — we can pull the snorkel off and hook up a long line and bucket.”

Bart Brainerd said there were no controllability issues with the aircraft during the flight tests. “Because it’s a progressive drop over about four seconds, there are no violent changes in the CG [central gravity].”

While the floor limit in the Black Hawk is 8,400 pounds, BHI² is estimating that the aircraft’s operating weight with a full tank of water will be around 8,200 pounds.

The company brought its H-60X research and development aircraft, equipped with the new firefighting tank, to the static display at this year’s HAI Heli-Expo 2019 in Atlanta, Georgia.

The aircraft is based in Leesburg, Florida, and is carded with the U.S. Forest Service; it can be pressed into service to fight fires if needed.

Bart Brainerd said the primary customer for the tank is the U.S. Forest Service, but given the level of interest in the tank, BHI² is going to start studying what building the tank for other companies might look like. Rob Reyno Photo

BHI²’s H-60X also features the company’s full vertical reference kit, which includes a bubble window with a cutout and a cut-back step faring that provides better load visibility.

The company’s modular firefighting tank received a positive reception at Heli-Expo 2019. When asked at the show if the tank design could be implemented on other aircraft like the Airbus H125, Bart Brainerd said: “On basically any aircraft with a square opening, rectangular opening or sliding cargo door, it could potentially be done. The Black Hawk has a pretty robust floor, and we have the restraint system [and] the FAA requirements with it in the cabin, but we definitely could look at it on a model-by-model basis to see if it’s possible.”

BHI² is not offering the tank for commercial sale at this time.