US Forest Service acquires two new King Air 260 aircraft for mapping fires

New King Air 260 delivered to the US Forest Service
New King Air 260 delivered to the US Forest Service, August, 2022. Textron photo.

Two new aircraft have been delivered to the US Forest Service for mapping wildland fires. The Beechcraft King Air 260 can cruise at 356 mph at 35,000 feet, can take off in 2,111 feet, and has a maximum range of 1,980 miles.

The aircraft have the latest infrared (IR) sensing technology, the Overwatch Imaging TK-9 Earthwatch Airborne Sensor, along with legacy U.S. Forest Service sensors, that can accurately map wildfires, even at night and through smoke. The system can perform high-resolution scans of fires in a range of spectrums including thermal and infrared from 2,000 to 20,000 feet in altitude.

The TK-9’s speed of data delivery and automation of mapping processes will make it possible for the Forest Service to quickly release imagery to the public, if they desire. We are checking, but it may be possible for the system to live-stream video.

Images produced by Overwatch Imaging's TK-9 payload
Images of the same fire produced by Overwatch Imaging’s TK-9 payload, featuring SWIRNI, Visual, MWIR, and LWIR sensor technology. Overwatch Imaging photo.

The two Citation V aircraft that Coulson Aviation configured and sold to New South Wales in 2021 to serve as lead/intelligence planes were outfitted with the TK-9 Earthwatch multispectral imaging systems.

TK-9 Multispectral Imaging
Overwatch Imaging TK-9 Multispectral Imaging payload.

“It took roughly 90 minutes to produce aerial fire images under the old process, once we had planned the flight path, sourced approval, undertaken the flight, scanned the fire, downloaded the imagery, and entered it into our mapping systems,” said New South Wales Rural Fire Service Chief Superintendent Christopher Ryder. “Now with the Citations and the TK-9 scanning technology, that process will take more like 30 minutes. The new system will take much of the human intervention out of the scanning and mapping process and provide a better and more timely understanding of where the fire is for the public.”

Previous Forest Service IR mapping aircraft

For decades the US Forest Service has usually operated two infrared mapping planes — a variety of twin-engine King Airs and for a while a Cessna Citation Bravo jet. The Citation suffered a serious avionics issue in June, 2019 and was not used the rest of that year or in 2020. We are unsure if it was ever used again to map fires. The FS filled the gap with privately owned aircraft on exclusive use and call when needed contracts.

Currently the FS is using the agency-owned King Air 200, N149Z, manufactured in 1985 and a King Air B300 owned by Tenax Air Logistics, N350SM.

Infrared plane, N149Z
US Forest Service  infrared plane, N149Z, at Boise, July 19, 2014

We contacted the Forest Service to get an update on the infrared fleet, but they were not able to immediately answer our questions.

US Forest Service infrared aircraft fire mapping
The two USFS aircraft equipped with infrared sensors used to map vegetation fires. USFS graphic from ~2020.

Thanks and a tip of the hat go out to Tom.

Oregon Department of Forestry trains personnel on fire detection aircraft

Oregon Department of Forestry's Partenavia P 68 Observer (N9000V)
Oregon Department of Forestry’s Partenavia P 68 Observer (N9000V). ODF photo in 2022.

The Oregon Department of Forestry’s (ODF) aviation unit held their annual multi-mission aircraft training May 16-20 in Salem, Oregon. This opportunity gave the department a chance to train personnel who will help with wildfire detection using the ODF-owned Partenavia P-68 Observer aircraft (N9000V).

The Partenavia is unusual — most of the “skin” on the aircraft in front of the pilot is transparent plexiglass, affording uncommonly good visibility. The plane has had many uses in the last 40 years, but its most recent function is as the platform for ODF’s nighttime fire detection work.  It is equipped with a Forward Looking Infrared (FLIR) camera system that is paired with an augmented reality mapping system.

During fire season, the Partenavia will fly at night to detect wildfires started by lightning. During their time in the air, the observer, or camera operator, will look for hot spots using the infrared system on the belly of the plane.

Oregon Department of Forestry's Partenavia P 68 Observer (N9000V)
Oregon Department of Forestry’s Partenavia P 68 Observer (N9000V) at Ken Jernstedt Airpot, Hood River, Oregon June 28, 2006. USFS photo.

“The accuracy of the Partenavia’ s FLIR infrared camera system allows for the observer to detect fires as small as a campfire from 12,000 feet in the air,” Jamie Knight, Aviation Operations Specialist, said.  “Once a wildfire is detected, the observer can pin the location and alert nearby fire protection agencies so that they may quickly respond to the fire.”

Aside from detecting smaller fires, the Partenavia is also used as “eyes in the sky” for larger incidents. Once over the fire, the observer can provide a high-level view of a fire and report to the firefighters on the ground about the progress and any changes in fire behavior.

During the summer months, the aircraft is centrally based in Redmond to allow access to the entire state.

Oregon Department of Forestry's Partenavia P 68 Observer (N9000V)

Oregon Department of Forestry's Partenavia P 68 Observer (N9000V)
Oregon Department of Forestry’s Partenavia P 68 Observer (N9000V) with USFS forest pathologist Mike McWilliams at Roseburg Regional Airport, Oregon. June 28, 2013. USFS photo.
Oregon Department of Forestry's Partenavia P 68 Observer (N9000V)
Oregon Department of Forestry’s Partenavia P 68 Observer (N9000V) was prepared for a night fire detection mission in 2021. ODF photo.

Infrared video of helicopters attacking fire in New South Wales

infrared video helicopter dropping water fire
Screenshot from the infrared video showing a helicopter dropping water on a fire in New South Wales.

This infrared video shows the effects of helicopters dropping water on a fire at Backwater in New South Wales, Australia. In the video colder objects, such as water, show up black or darker than warmer objects.

Fire whirl filmed with infrared camera

infrared video of fire whirl
Screen shot from infrared video of a fire whirl. Courtesy of RPX Technologies.

Jim O’Daniel of RPX Technologies sent us the link to the video below which shows a small fire whirl filmed by one of their HyperSight infrared thermal cameras. The devices, which can see through smoke, can be mounted on a fire engine.

Mr. O’Daniel said, “The camera we developed is intended as a safety tool for escaping and navigating through smoke. The camera is vehicle-mounted and always ready. It allows the driver to see while keeping windows up and both hands on the wheel.”

And, just to be clear, it is not a “fire tornado”. David W. Goens of the Missoula office of the National Weather Service explained what a fire tornado is:

These systems begin to dominate the large scale fire dynamics. They lead to extreme hazard and control problems. In size, they average 100 to 1,000 feet in diameter and have rotational velocities up to 90 MPH.

In addition, they can last for an hour or more and have been known to move across the terrain for miles. You do not want to be anywhere near a fire tornado. They can be deadly.

After the Carr Fire at Redding last year, a report was issued about a real fire tornado that was related to the death of at least one firefighter.

A large fire tornado was one of the primary causes of the entrapment and death of FPI1 on July 26, 2018. The fire tornado was a large rotating fire plume that was roughly 1000 feet in diameter at its base. tornado Fujita scaleWinds at the base of the fire tornado reached speeds in the range of 136-165 mph (EF-3 tornado strength), as indicated by wind damage to large oak trees, scouring of the ground surface, damage to roofs of houses, and lofting of large steel power line support towers, vehicles, and a steel marine shipping container within ½ mile of the entrapment site. The strong winds caused the fire to burn all live vegetation less than 1 inch in diameter and fully consume any dead biomass. Peak gas temperatures likely exceeded 2,700 °F.

Researchers demonstrate that it is possible to accurately measure wildfire rate of spread from an orbiting aircraft

measure wildfire rate of spread from aircraft
Figure 3. Fire spread sequence for Detwiler Fire. Active fire fronts and fire spread vectors are portrayed for the seven-image sequence on 20 July 2017. The background image is a fusion of NAIP colour (depicting vegetation fuels and topography) with a colour density sliced version of the seventh FireMapper 2.0 image.

Now that federal land management agencies are being forced by an act of Congress to begin providing to fire managers the real time location of fires and firefighting resources, it opens a range of cascading benefits beyond just enhancing their safety and situational awareness.

Fire Behavior Analysts that could continuously observe the fire with infrared video from a manned or unmanned aircraft orbiting above the air tankers could make much more accurate, valuable, and timely Fire Behavior Forecasts. The fire spread computer models could be fine-tuned to be more accurate and their outputs could be displayed on the map along with the locations of firefighters who carry tracking devices, enabling the Operations Section Chief to make better-informed strategic and tactical decisions.

But until recently it was not known if georeferenced infrared imagery from an orbiting aircraft was accurate enough to be used for determining the rate of spread.

The short answer is, yes. A paper published last week indicates that the accuracy is sufficient. (FYI — the document is written for other scientists and not for practitioners.)

Now the question becomes, will the federal land management agencies actually implement the program to track the real-time location of fires and firefighters, or will they slow-walk it into oblivion like the Congressional orders to purchase a new air tanker, convert seven HC-130H Coast Guard aircraft into air tankers, and the repeated requests from the GAO and Inspector General to provide data about the effectiveness of firefighting aircraft?

measure wildfire rate of spread from aircraft
Figure 7. Wildfire spread during the Rey Fire on 21 August 2016. (a) Time 1 fire front. (b) Time 2 fire front (7 min later). (c) Fire spread vectors and ROS statistics. (d) 3-D perspective image depicting active fire front and spread vectors. (e) Histogram depicting frequency distribution of ROS estimates for all spread vectors in the two-pass imaging sequence.

Unfortunately even though United States taxpayers funded the research through the U.S. government’s National Science Foundation (grant number G00011220), only some of us will be able to read the fruits of the research since it is not an Open Access document. After it is viewed 50 times free access will be shut off.

Open Access logo
Open Access logo

It is published at Taylor and Francis Online, a private company based in the United Kingdom. So by the time you read this the company may be charging people to read the document. (UPDATE at 7:42 a.m. MST February 21, 2019: General access to the document has been shut off. The company is now charging $50 to view it for 24 hours.)

Not allowing taxpayers to read government funded research unless they pay for it again is reprehensible.

The document is at Taylor and Francis Online: Assessing uncertainty and demonstrating potential for estimating fire rate of spread at landscape scales based on time sequential airborne thermal infrared imaging. By: Douglas Stow, Philip Riggan, Gavin Schag, William Brewer, Robert Tissell, Janice Coen, and Emanuel Storey