You're deep in the soup at the FAF, yet you can see paint, pavement, and the Bonanza holding short of the runway clear as day.
by Jeff Van West
Pat Farrell set out to bring forward-looking infra-red (FLIR) technology to GA airplanes for personal reasons. He feels it could have saved his buddy's life. "I was literally picking through the woods looking for his body when I started thinking of this stuff," says Farrell. "It was low, it was nasty, it was dark, and he'd flown all day in his Aerostar. And he was one of the careful guys. Well-trained and careful."
Farrell's friend flew into terrain he couldn't see after getting below glideslope. What you can't see you can't avoid. In a nutshell, that's the whole point of the FLIR. It let's you see what is normally obscured so you can avoid it.
Even when all is well on approach, the unknown adds immensely to the pucker factor. On approach to the airport where I'd meet Pat and fly the FLIR system in his airplane, the glideslope receiver failed right at the FAF, requiring a rushed reconfiguration for the localizer-only approach to a completely unfamiliar airport. I was wishing we already had the FLIR just to see what lay beneath the murk as we dropped fast - and blind - toward the MDA.
Since most of us haven't flown a FLIR-equipped Gulfstream G-V into Aspen at night, here's a way to wrap your brain around the concept of a FLIR. Think about navigating a complex terminal area while IMC using only a pair of VORs. Now imagine doing the same thing with a GPS and color moving map. Sure, you can successfully do either, but with the GPS-powered map, your position is obvious.
The camera is mounted on the air-
frame as it can't see through plastic.
Flying an approach with the FLIR image displayed on a small cockpit LCD screen is analogous. The infra-red (IR) camera is seeing heat, but since different objects all radiate heat differently, the result is a black-and-white image with the resolution of a cheap web cam. An IFR pilot can navigate down to minimums fine without seeing the runway, but with the FLIR, the runway is, well, right there in front of you.
Better yet, anything between you and the runway - rocks, buildings, or trees - are obvious as well. Other airplanes show up as white dots on the FLIR screen while still over three miles away. Deer on a runway at night are clearly visible. Even birds appear on the screen, although you might not be able to miss them in time.
Taking this GPS analogy a bit further, in an emergency, the ease of a "nearest" button and a constant distance and groundspeed readout might save your life someday. Having flown the system on a cruddy day, I can say I'd be mighty glad to have one if I ever lost my engine while IMC or at night.
In fact, the forward vision system may have saved one life already. Farrell's company, Forward Vision (www.forward-vision.net), is partly owned by the aircraft kit company CompAir. One of CompAir's test pilots took up an aircraft on a hazy night with a freshly-installed FLIR.
He noticed that the horizon as shown on the FLIR was tilted, figured the FLIR pod mount must be coming off the airplane, and pointed his flashlight out the window to see how bad it was.
The FLIR was still attached perfectly. He then realized the AHRS system for the glass cockpit (continued below)
WHEN LOOKING INSIDE IS CLEARER THAN LOOKING OUTSIDE
Showing you FLIR and IMC side-by-side would be a bit boring, since one side would just be grey, so here are some views where you can actually compare, FLIR on the left and visible on the right. Both the FLIR and visible-light cameras were mounted on the right wing.
The top pair shows the runway on a cloudy day. Note how the paint stripes are dark (cool) and individual
clouds in a layer are seen on the FLIR where it's just a hazy sky on the visible image.
The second pair is during a snowstorm at night. The Saab commuter taxiing is clearly visible on the FLIR.
The third pair is an approach flying the bottom of the glideslope signal. Note how trees, towers, the runway, and even cars on the road are clearly visible. This view is at night, but the appearance would be the same even if still in the soup.
had failed. Nearly inverted by then, he completed the roll and flew home with the FLIR as his primary attitude reference.
The actual system consists of a 3.6-pound camera and fairing mounted somewhere on the airplane and a small LCD screen in the cockpit. (For those of you familiar with IR cameras, this is a BST camera that's immune to damage from accidently pointing it at the sun.)
The camera can't see through glass or plastic, so it has to go somewhere outside the airplane. This is the biggest issue with certified installations.
The company is exploring mounting the camera in place of either a landing or taxi light on aircraft that have both. There is also the possibility of a storm-window mount that would be removable and require no paperwork.
Simple to Use
Once it's on the airplane, the image appears on a screen in the cockpit. You periodically check the image as part of your IFR scan. If you've ever peeked while doing simulated IMC, you'll feel right at home. The screen can go anywhere that makes sense to you. Farrell's airplane had it sitting up on the glareshield.
On the day I flew the system, too many nearby thunderstorms kept us from flying full approaches, but scud-running through mist and rain demonstrated some of the system's strengths and weaknesses.
The picture takes some getting used to. Depth perception is the hardest item to interpret, and houses, roads, and towers on the display look further away than they really are. The image is also an inverse of what you might expect in some situations. For example, the paint on the runway is darker (cooler) than the pavement. It's still obviously a runway, though.
Rain significantly attenuates the image, meaning you can't see through it very well. Comparing the view on the FLIR to the view outside, I'd say the picture was always better on the FLIR, but when we passed through virga, it wasn't much better than the forward view.
Looking through clouds was another matter entirely. At one point I was focusing on the FLIR and started to fly into a cloud because on the screen I was looking right through it. Interestingly, clouds at a distance are visible if there is nothing but sky behind them, meaning you could use the system to stay VFR at night.
According to Farrell, rain and "old" fog have the greatest attenuation and yield the worst image. Snow is not quite as bad. Clouds and recently-formed fog are virtually transparent to the FLIR.
Most aviation systems using IR run from $65,000 to over $1 million, depending on their capabilities and certification. Forward Vision costs $18,500. Why the difference? Many of the pricey FLIRs are sophisticated "enhanced vision" systems that effectively mean lower minimums and give Part 135 and 121 operators an opportunity to shoot approaches into airports reporting under minimums. Forward Vision is advisory only.
That's the rub for "low-cost" FLIRs. It's a hard to see the value of one of these systems unless you regularly fly with it into low IFR or black-hole airports at night - or have had an IMC or night emergency.
Forward Vision has sweetened the pot in a few ways. The systems have a battery backup so you can lose all electrical power and still have the FLIR image and LCD screen for "visual" flight to an emergency landing. They are finalizing input from the various GPS to put groundspeed and track on the FLIR's LCD display. There will also be a 30-minute recorder letting flight instructors play back approaches for students (or perhaps be a tool for the NTSB if even the FLIR couldn't help you out.)
The company believes once people start flying with the systems, the demand will increase dramatically. To prime that pump, they announced in July that the next 100 systems would be sold for $10,000.
Forward Vision believes that a few "saved my butt" stories will be better than any ad campaign. "We're going to become the number one educator and supplier [of FLIRs] to GA," says Farrell, "and we're going to save some lives."
If you want a jump start on what should be the next great safety innovation for GA, check out one of these FLIR systems. Honestly, it's that amazing.