Aviation Technology’s AltAlert provides audible and visual alerts when cabin altitude climbs to dangerous levels. The device can fit in a pocket or be mounted on the aircraft window.
The AltAlert device is easy to carry into any aircraft and can either clip onto a shirt pocket or be suction-cupped to a window near the pilot’s field of view. Both aural and LED visual alarms warn the pilot that the cabin altitude is climbing above specific thresholds. AltAlert is available from many pilot shops and retails for $399.95.
The AltAlert is based on a NASA patent, but what Sawaya and her engineering team did was develop algorithms that make the device work reliably and consistently with a long battery life of 18 months. “It took about four years from the concept to getting it completely developed and bringing it to market,” she said.
“I started researching the number of accidents logged with the NTSB related to pressurization,” Sawaya explained. “The Payne Stewart accident was the most highly publicized, but the total number is enormous. It was really just a coincidence that the TBM 900 went down last September; we were finishing up by then. It was yet another example of the need for this device and its lifesaving capabilities.”
AURAL AND VISUAL WARNINGS
AltAlert is built around a pressure sensor. The algorithm drives six alarm modes, from nothing until 10,000 feet to combinations of a flashing LED and audible chirps at various higher altitudes. Above 10,000 feet, the red light flashes every 15 seconds along with a single “courtesy” chirp. Above 11,500 feet, the light flashes every five seconds and two chirps warn the pilot that cabin altitude has reached that level. Above 12,500 feet, the light flashes every second and there is a triple chirp. At this point the AltAlert also starts a 30-minute timer and if the aircraft’s altitude is between 12,500 and 14,999 feet after that interval, it switches to the above-15,000-foot alarm (the highest alarm). The above-14,000-foot alarm is flashes a red LED every second, but adds a constant double chirp. Above 15,000 feet, the LED and the chirp both remain on constantly. The first four modes can be muted, but once above 14,000 feet, the device cannot be muted.
I tested the AltAlert in a Cessna 172 with another pilot. We both used a pulse oximeter to measure our oxygen saturation as we climbed to 12,500 feet west of Van Nuys, Calif. We were going to go higher, but the 172 would have taken too long to climb the remaining 1,500 feet and we had no supplemental oxygen. Also, we felt that our oxygen saturation numbers precluded remaining at high altitudes any longer.
The AltAlert worked as advertised, and the LED was clearly visible and the chirps audible even with my passive headset on. It’s difficult to say whether the AltAlert would capture a pilot’s attention during a cabin pressurization problem, but it would certainly be useful to have as a backup device and it should increase the chances that pilots or even a passenger flying in the other seat might notice that there is a cabin-altitude problem. Where it seems AltAlert could really help is during a slow decompression, especially in an airplane without an automatic emergency-descent autopilot mode.
“We’re really excited about it,” said Sawaya. “It’s been lot of hard work and a lot of sacrifice.” One pilot bought an AltAlert after experiencing a slow leak caused by a failing door seal. “He was getting hypoxic,” she said, “and was able to recognize it and do an emergency landing before any tragic consequences. He said, ‘I wish I had this a year ago. I’m one of the lucky ones.’ To be able to put something like this on the market for a reasonable price is something we’re really proud of.”
Комментариев нет:
Отправить комментарий