Mapping wildfires from 70,000 feet

Raven Aerostar balloon
File photo of a partially inflated Raven Aerostar balloon just after launch. Still image from Aerostar video.

This article was first published at Fire Aviation.

The US Forest Service is partnering with NASA to evaluate the use of two high-altitude long endurance drones to improve wildland firefighters’ situational awareness.

1. A balloon

Last week a balloon laden with a sophisticated package of electronics hovered 60,000 feet over the Moose Fire in Idaho. Its mission was to assist firefighters in improving and maintaining situational awareness. Some of them may have seen the shiny object the size of a football stadium, even though it was more than 11 miles above the incident.

The company that built and operates the aircraft, Aerostar, calls it STRATO, or Strategic Radio and Tactical Overwatch, a technology that is in the research and development phase.

Thunderhead Stratospheric balloon can assist wildland firefighters
Illustration of how a Thunderhead Stratospheric balloon can assist wildland firefighters.

The STRATO is basically a giant mylar balloon with solar panels, batteries, radio equipment, cameras, and sensors. It has the capability to collect infrared and visual data, broadcast an LTE (cell phone) signal, has a high-band radio that can enable push to talk communications, and can operate a WiFi network. The huge helium balloon can hover over an incident in the stratosphere taking pictures, delivering data to incident managers, and providing communications options to the Incident Command Post and crews on the ground.

Aerostar Thunderhead Stratospheric balloon Moose Fire
Flight path of an Aerostar Thunderhead Stratospheric balloon over the Moose Fire the week of August 7, 2022.

Last October Fire Aviation wrote about the system operated by Aerostar, a company based near Sioux Falls, South Dakota, which has been working with lighter than air technologies since 1956. We contacted the Communications Manager for the company, Lisa McElrath, who told us that in June, July, and August of 2021 they launched one of their Thunderhead Balloons from South Dakota and flew it west to monitor wildfires. While traveling more than 16,000 miles during its 70-day flight it engaged in station-seeking above four active fires for the company’s research and development.  It collected visible and thermal imagery data for extended periods of time on the Robertson Draw Fire (Montana), the Dixie Fire (California), the Dixie-Jumbo Fire (Idaho), and the Dry Gulch/Lick Creek Fire (Washington).

In October we asked Ms. McElrath if Aerostar had been cooperating with the federal land management agencies in mapping fires. She said not yet, but that representatives from the National Interagency Fire Center had reached out to them and expressed interest in discussions after the fire season slowed down. But this year the US Forest Service is officially cooperating in the pilot project.

“We can provide real-time imagery from the balloon today in the visible and infrared,” Ms. McElrath said. “In the future, the goal would be to automate the detection and download of critical imagery, fire perimeters, likely fire-starts, and other key information via onboard processing so that more actionable information would be available. We see stratospheric balloon technology being the key to cost-effective, scalable wildfire surveillance that reduces time between new fire detection and response. Effectively, balloons can alert firefighters to a new fire while it is still small, before the fire grows into something newsworthy and very expensive.”

She said the balloons can also serve as radio repeaters for personnel on the ground and could collect information from tracking devices on firefighting resources which could then be displayed on a map.

More flights over fires are being planned, said Sean Triplett, Team Lead for Tools and Technology, U.S. Forest Service, Fire and Aviation Management. He said NASA is matching the funding the Forest Service is putting toward the flights this year.

2. Fixed wing aircraft

Swift Engineering's SULE HALE-UAS
Swift Engineering’s SULE HALE-UAS. Swift Engineering photo.

Another High Altitude Long Endurance (HALE) aircraft the Forest Service is looking at is Swift Engineering’s SULE HALE-UAS, capable of staying aloft for more than 30 days at a time. The Forest Service, again partnering with NASA, has issued a contract with the company and as of March 31, 2021 they had conducted more than 10 demonstrations of the solar powered fixed wing aircraft.

The key to long duration flight using solar power on an airplane is to have a top surface area large enough for the solar cells needed to power the electric motors day and night, using a battery for night operations. Large wings mean more solar cells, but also more wind resistance. So the answer, using today’s technology, is to fly very high at 60,000 to 70,000 feet where the air is thin, the sunlight on the solar panels is strong, and there is less wind resistance.

The SULE, which took its first flight in July of 2020 has a 72-foot wingspan, operates at 70,000 feet, and can carry a payload of 15 to 22 pounds.

“A series of mid-altitude and high-altitude flights is being undertaken, Mr. Triplett told Fire Aviation on Wednesday. “At this point, the platform is only providing remote sensing products. However, if successful, additional systems may be incorporated.” Those added systems could include a radio system to provide connectivity enabling the tracking of firefighting resources on the ground in addition to live imagery of the fire.

Mr. Triplett said one advantage of having NASA as part of the project is that they can handle the airworthiness of the aircraft and interactions with the FAA.

The Swift Engineering video below shows what may be the first flight of the SULE two years ago.

A step toward the Holy Grail of Wildland Firefighter Safety?

Our view is that providing to wildland fire supervisors the real time location of both the fire and firefighting resources is the Holy Grail of Wildland Firefighting Safety. Lacking this information has led to at least two dozen firefighter fatalities. These High Altitude Long Endurance aircraft 13 miles above the fire could be an important link to transmit live video of the fire to personnel and provide radio connectivity enabling the tracking of firefighting resources on the ground even when they are in steep rugged topography. Of course the resources would need to have the hardware necessary to transmit the coordinates of their locations.

The John D. Dingell, Jr. Conservation, Management, and Recreation Act which became law March 12, 2019 required that by March 12, 2021 the five federal land management agencies “…develop consistent protocols and plans for the use on wildland fires of unmanned aircraft system technologies, including for the development of real-time maps of the location of wildland fires.”

While this technology has been demonstrated, real time mapping appears to be far from being used routinely, at least within the Federal agencies. But at the state level, the Governor of California has requested $30 million in their next budget for 31 positions and funds for the state’s Office of Emergency Services to operate Real-Time Intelligence System (FIRIS) aircraft that have shown that they can provide real time fire mapping information. A pilot program for FIRIS first got off the ground September 1, 2019 thanks to funding secured in the 2019-2020 California state budget. This year two FIRIS ships have been assisting firefighters.


The Dingell Act also mandated that the five federal land management agencies “jointly develop and operate a tracking system to remotely locate the positions of fire resources for use by wildland firefighters, including, at a minimum, any fire resources assigned to Federal type 1 wildland fire incident management teams”, again, due by March 12, 2021.

Other solar powered high-altitude aircraft

An aircraft that the Forest Service is not involved with is the Zephyr, made by AIRBUS. It is an unmanned, solar-powered fixed wing aircraft designed to stay aloft at high altitude for months.

AIRBUS Zephyr, stratospheric unmanned aerial vehicle. Airbus image.

In its latest test flight that began June 15, 2022 the Zephyr took off from the U.S. Army’s Yuma, Arizona Proving Ground and has been flying patterns over the Yuma Test Range and Kofa National Wildlife Refuge ever since. Now 63 days later the flight has smashed Zephyr’s previous record of 25 days that it set in August 2018. When we checked August 17 it was cruising at 40 knots ground speed 70,500 feet above the Earth.

Flight path of ZULU82 Zephyr
Flight path of ZULU82 Zephyr, a solar-powered unmanned aircraft on August 16, 2022, day 62 of a flight that began June 15, 2022.

UPDATE at 7:35 p.m. MDT August 21, 2022

The flight of the Zephyr has ended.

“Following 64 days of stratospheric flight and the completion of numerous mission objectives, Zephyr experienced circumstances that ended its current flight. No personal injury occurred,” AIRBUS said in a statement.

Simple Flying reported that a catastrophic loss of altitude occured on August 19 after flying for 64 days straight:

On its final day of operations, it was tracking around over the vast Arizona Desert, about halfway between Phoenix and Mexicali, Baja California. Flying slightly lower than was typical, at some 45,000 – 50,000 feet, it had completed an S-shape maneuver at around 50 – 60 knots when something went catastrophically wrong. ADSB data shows a vertical descent rate which rapidly increased, topping out at a speed of 4,544 feet per minute. Although unconfirmed by Airbus, it does seem that the Zephyr met a rather unglamorous end.

Zephyr solar powered aircraft
The Airbus Zephyr S during a 2021 test flight. US Army photo.

Cactus Fire stopped at 35 acres east of Big Bear Lake in SoCal

S-2T air tanker drops on the Cactus Fire, April 30, 2022
S-2T air tanker drops on the Cactus Fire, April 30, 2022. @BrookesLori.

Yesterday firefighters stopped the spread of a wildfire in Southern California in the San Bernardino National Forest after it burned about 35 acres in Cactus Flats east of Big Bear Lake. Soon after it started it was putting up a smoke plume with occasional puffs of dense black smoke. The incident commander ordered a total of six fixed wing air tankers which assisted firefighters as they installed a hose lay around the perimeter.

Cactus Fire, April 30, 2022
Cactus Fire, April 30, 2022. @jojacaliente
Cactus Fire, April 30, 2022
Cactus Fire, April 30, 2022. San Bernardino NF photo.
Aircraft over the Cactus Fire at 317 p.m. PDT April 30, 2022
Map showing the location of aircraft over the Cactus Fire at 3:17 p.m. PDT April 30, 2022. ADS-B Exchange.

The video below was shot by the FIRIS aircraft at 2:22 p.m. PDT April 30, 2022.

Infrared video mapping of the Emerald Fire near Laguna Beach, California

The blaze burned 154 acres, coming very close to homes

Emerald Fire map
Still image from the video below of the Emerald Fire, from the FIRIS mapping aircraft at 1:46 p.m. PT Feb. 11, 2022.

The Emerald Fire near Laguna Beach, California was mapped by the Fire Integrated Real-Time Intelligence System (FIRIS) aircraft. The video below was recorded at 1:45 p.m. February 11, day two of the fire. The image switches back and forth from thermal infrared to regular video, with heat showing up as bright white. This data can help firefighters know where to concentrate their containment and mop up efforts.

After the fire was reported Feb. 10, 2022 at about 4 a.m. in the Laguna Coast Wilderness Area, strong winds pushed the blaze near homes in the Emerald Bay area of the coastal city. It ultimately burned 154 acres, coming very close to homes, as you can see in the video.

In the aircraft were Peter Cain (Pilot), Matt Hedman of AEVEX on the controller, and Air Tactical Group Supervisor Steve Price providing narration.

Map Emerald Fire, Feb. 10, 2022 Laguna Beach California
Map Emerald Fire, Feb. 10, 2022.
map Emerald Fire near Laguna Beach
Map showing the location of the Emerald Fire near Laguna Beach in Southern California, Feb. 10, 2022.

Two escaped prescribed fires in California

Calvert Fire map
Map showing location of the Calvert Fire March 1, 2021

The spread of an escaped prescribed fire 11 miles south of Big Pine, California was stopped Monday on the east side of Hwy. 395 by firefighters from the California Department of Forestry and Fire Protection.

The plan by the CAL FIRE San Bernardino Unit was to ignite the project at 8 a.m. Monday but a change in wind direction surprised the crews and caused the blaze to escape the project boundary and was declared an escape at 11 a.m.

The new fire named Calvert was mapped at 262 acres by the Fire Integrated Real-Time Intelligence System (FIRIS) operated in a fixed wing aircraft by Orange County Fire Authority. FIRIS has proven to be an incredibly valuable resource for providing real time video intelligence, fire spread projections, and situational awareness during wildfire suppression.

We need about a dozen more FIRIS units.

Calvert Fire
Photo of the Calvert Fire, by AA120, March 1, 2021.

Still another escaped prescribed fire in Southern California:

There is a report that another prescribed fire escaped in California, this time it was Tuesday near Clear Creek Station in the Angeles National Forest. The escape was named Clear Fire.

There were approximately three other wildfires in SoCal Tuesday in Meade Valley and the Perris area.

The article was corrected to indicate that the Calvert Fire was Monday, not Tuesday.

Red Flag Warnings in Southern California

The winds are going to be breezy to very strong, off and on through Thursday

Hot-Dry-Windy forecast for Southern California
Hot-Dry-Windy forecast for Southern California, January 16, 2021

After record high temperatures were set Friday in multiple Southern California locations, Red Flag Warnings continue on Saturday. Residents in Santa Clarita can expect the temperature to reach 83 degrees today, with the humidity in the low teens, and 22 mph winds out of the northeast gusting to 33. Strong winds will continue through Saturday night but will taper off a bit Sunday, 18 to 22 mph gusting out of the northeast at 28 to 34.

Monday afternoon a strong offshore pressure gradient will begin growing, bringing very strong winds out of the northeast again, with the humidity in the low 20s and teens.

Wind speeds next week:

  • Monday afternoon: 24 mph gusting at 32
  • Monday night: 25 to 47 gusting at 37 to 62
  • Tuesday: 47 gusting at 63
  • Tuesday night: 29 to 41 gusting at 38 to 54
  • Wednesday: 18 to 26 gusting at 24 to 34

Record high temperatures in Southern California

At least two large air tankers, 01 and 02, were flown in from Missoula on Friday to be available if needed by firefighters. Two Fire Integrated Real-Time Intelligence System (FIRIS) mapping aircraft are also on standby.

Fire Integrated Real-Time Intelligence System (FIRIS) aircraft
Fire Integrated Real-Time Intelligence System (FIRIS) aircraft.
Red Flag Warnings, January 16, 2021
Red Flag Warnings, January 16, 2021. National Weather Service.
Red Flag or near Red Flag conditions
Weather stations in Southern California experiencing Red Flag or near Red Flag conditions, January 16, 2021. National Weather Service.
Santa Clarita Wx forecast, January 16, 2021
Santa Clarita, California Wx forecast, January 16, 2021. National Weather Service.

New South Wales posts map showing predicted spread of bushfires

Comparing firefighting in North America and Australia

When a group of firefighters from North America arrived in Australia earlier this year to assist with an exceptionally large number of bushfires, one of them was quoted by a local media outlet as saying, “I understand it’s pretty traumatic for you guys, but it’s something we deal with – it’s our comfort zone”. It was not clear to whom the firefighter was speaking, civilians or in-country firefighters, but it struck me as a little odd and could be interpreted as patronizing from someone who had been in the country for less than a day.

Make no mistake, Australians have been dealing with vegetation fires as long as the North Americans have, and their blazes can be just as calamitous as those on the other side of the equator. Firefighters on both continents can learn from each other. From my limited vantage point 8,000 miles away it is clear that Aussies do a lot of things very well, especially designing their fire engines and keeping the public informed about  the status of active fires.

In the United States if a citizen needs current information about a wildfire how do they get it? The local sheriff, local fire department, or a state agency? It makes a difference about where to look if the fire is on federal land, state protected land, city, county, national or state park. If they try social media, what account? InciWeb sometimes has information about wildfires managed by federal agencies, but not all. Information about individual fires may not have been updated for 12 to 18 hours, however some incident management teams are better than others.NSW RFS Twitter And evacuations are managed by local law enforcement. When someone is threatened by a rapidly spreading wildfire they don’t have time to randomly check an alphabet soup of acronyms on dozens of web sites or social media accounts, even if they know the names, handles, or web addresses.

The map below is an example of something done very well in Australia. In New South Wales the Rural Fire Service distributes a great deal of current information to the public through Twitter, Facebook, and their web site.

NSW RFS fire spread projection map
From the NSW RFS:
Advice – Green Wattle Creek (Wollondilly LGA)
Extreme Fire Danger is forecast for this fireground on Thursday 19th December 2019. Conditions will be dangerous due to high temperatures, strong and gusty winds and low humidity. This potential fire spread prediction map shows the communities that may come under threat from embers or fire fronts. Conditions are then forecast to worsen again on Saturday.

It would be very unusual for a firefighting agency in the U.S. to distribute to the public a map, like the one above, that showed projections of fire spread of two major fires over the next 24 hours. Most agencies in the U.S. are hesitant to even publicly predict the general direction a fire will spread, let alone a map showing the location and extent of where the fire is expected to be in a matter of hours.

The technology to produce maps like this exists, but depending on the accuracy needed, it can require a supercomputer to crunch the numbers. In September the Orange County Fire Authority in California began a 150-day pilot program to use and evaluate the Fire Integrated Real-Time Intelligence System (FIRIS). It utilizes a supercomputer at the University of California San Diego running WIFIRE spread projections based on fire perimeter data collected by an aircraft. The output estimates where the fire will be in the next six hours. It has been run on real fires a few times, with the latest being the Cave Fire at Santa Barbara, California.

Another area where the NSW RFS excels is posting aerial videos of active fires. The agency frequently puts them on Twitter and Facebook, giving the public a general idea of how actively the fire is burning. Many of them show air tankers and helicopters dropping water on the fires, showing taxpayers how their money is being spent.