Thursday, October 1, 2009
North to Alaska
The weather outside is frightful... It’s high noon on November 24th: The wind is 30-plus knots with blowing snow; the temperature is minus 40 degrees Fahrenheit; there are polar bears lurking outside your hangar; and the sun won’t come up until late February.
Just the thought of that kind of environment is enough to make practically every pilot in the lower 48 thankful they don’t have to strap on a helicopter and go off into the darkness in search of a lost hunter. But it’s just another day at the office for North Slope Borough’s Search and Rescue team.
"This is, to say the least, a very harsh environment," said the operations’ chief pilot, Chuck Benson. "It’s not the kind of flying for everybody."
But thankfully, for the nearly 7,000 residents living in the six villages that make up the North Slope Borough, there are pilots and technicians willing to brave the elements to respond when the need arises. "The primary focus of course is search and rescue and medical evacuations," Benson explained. "In the winter we are usually responding to a PLB (personal locator beacon) — belonging to a lost hunter or traveler. We’re available 24/7, but it still seems like the calls never come in at a convenient time."
The typical search ranges in distance from a 15-mile radius around Barrow then south to the 9,000-foot peaks of the Brooks Range. While a lost hunter 15 miles away may not seem like a dire situation, remember that when it’s minus 40, every minute counts.
"We use all four aircraft to fulfill our missions," he said. "The two helicopters are primarily low-level SAR. We also do field medivacs, which include hunting camps, tundra, on-ice — wherever we are required to do on-site pickups."
Based at Barrow Airport, one of only three hard surface airports in the 90,000-square-mile Borough, North Slope’s fleet currently includes a Lear 31, King Air B200 and two Bell 412s. "We have 10 highly experienced pilots. Our high-time guys are in the 24,000-hour range and our ‘young’ guy is around 10,000 hours," Benson said. "All of our pilots except one are dual rated."
"We average 300 hours annually per aircraft. Mission-wise it’s kind of broken up between the emergency flights, SAR, services, and health and welfare," he said. "We do the long-range missions from Barrow to Anchorage — about 700 miles — in the Lear."
Benson also stressed that being located so far from a major city means the group has to be very self-sufficient. "Jim Contreras is our director of maintenance and he has six technicians on staff — all are A&P and IA qualified."
Weather’s Not Fit
When Benson said, "It’s not the kind of flying for everybody," he could have very well been referring to the aircraft as well as the people who fly them. The extreme cold temperatures have forced the North Slope Borough SAR team to implement some special procedures.
"We don’t let the aircraft set out in minus 40 if we can avoid it," he explained. "We come out of warm hangars and start the aircraft as soon as we can and we don’t shut down once we are out in the field — shutting down in that weather is just an invitation for disaster."
Even with their precautions, the cold continued to play havoc with many critical systems, especially on their two Bell 412s. "The Tarsyns [spinning gyros] were killing us. We were having all kinds of problems," Benson said. "For lots of reasons: they’re old technology and they’re very sensitive to the cold. We were experiencing some very weird behavior from our autopilots and they are very important when we are doing low-level searches. When you get down to 100 feet at night you really need that autopilot as backup. You need to trust it."
While the autopilot problems were major, they weren’t the only reliability issues facing North Slope’s two 412s. Before joining the fleet in 2005, both helicopters were in the 7,000-hour range TT and had been flown in warm weather. N401ES had served with the Tokyo Police Department and N402ES flew with the Aga Khan Foundation in Pakistan. Like most of us, the dramatic change in climate didn’t agree with the aging helicopters’ components.
"When you have problems, first of all it’s figuring out what the problem is, and then getting a solution to that problem," Benson said. "If it’s a piece of hardware, can you find a replacement and get it? With us everything is time-oriented. When we have to order parts we know it’s going to take forever to get here. We don’t have FedEx or UPS up here. Sometimes we just have the parts sent to Anchorage and we fly down to pick them up."
"The down time was killing us. The cost was killing us," he added. "All together it was really hurting our availability."
Everything Old is New
When you’re in the search and rescue business, excessive downtime is something you just can’t tolerate. So even though it would mean taking one of his two helicopters out of service for a long time, Benson and his team decided to send N401ES down to Arrow Aviation Co. in Broussard, La., for a major upgrade. "We knew it would be a sacrifice, but we’re hoping the reward will offset it," he said.
At the heart of the upgrade is the replacement of all the old technology components and systems with a four-screen, Cobham Avionics EFIS system including new-generation LITEF fiber-optic gyros. While Arrow is a well established and respected Bell Helicopter service facility, this project would be totally new — it was the first ever installation of the Cobham EFIS with 3D synthetic vision in a Bell 412. Arrow’s team would not only be designing and installing the system, but also managing the certification process to earn an FAA STC for the installation and IFR approval for the system.
While marrying state-of-the-art digital EFIS displays with the helicopter’s 25-year old analog systems may seem daunting, it really wasn’t as difficult as you may think. As Arrow’s avionics manager, Glenn Nestor, explained it, "We did a lot of pre-planning. We tried to utilize as much of the aircraft’s existing wiring and bulkhead disconnects as we could, keeping cable routing as close to original as possible."
The installation actually includes two totally independent systems with a cross-fill capability. The system includes dual GPS, dual analog interface units (AIUs), dual air data computers (ADCs) and dual attitude and heading unit (AHRU) fiber-optic gyros. The benefit of this installation is that with two complete sets of sensors, if one goes down all the crew has to do is push a button and the remaining "good" input source will feed both displays.
The independent systems also continually monitor each other for any miscompares. Say the pilot and copilot accidentally enter different barometric pressures on their altimeters. The system will see that and alert the crew of the situation.
"We tried to make the installation as modular as possible for removal and installations," said Mark Evans, Arrow’s project manager. "That was probably the biggest challenge and most of that was done early on in the engineering."
For example, in the design and fabrication of the new instrument panel, Arrow’s team didn’t change any part of the center panel section. "We just made new pilot and copilot panels," he explained. "The area behind the panel is pretty tight. We designed the panels so the Cobham EFIS display tray assemblies are actually mounted as one unit. That gives easy access to the cannon plugs in the back."
To further simplify the installation, wherever possible Arrow’s designers utilized the existing locations of the mounting fasteners of the units they were replacing. For example, The AHRU’s mount was designed to replicate the lateral and longitudinal axis of the Tarsyn gyro units they replaced.
Evans also said that in order to accommodate up to 100 pounds in additional avionics, Arrow developed an avionics/accessory shelf as a separate STC. The Garmin GDL 90 ADS-B data link system and the two GPS WAAS sensors are mounted to the new shelf in one compact area.
Because clean GPS reception can be an issue up in the North Slope, another challenging part of the installation was the critical location of the GPS antennas. Arrow’s designers worked with Bell Helicopter engineers to design a dual antenna mount for the top tail rotor gearbox to ensure the antennas remain in clear air. Evans said that the pilots reported that they never lost GPS signal during the 4,000-mile flight back to Alaska.
Because Benson was trying to take full advantage of having his aircraft in the capable hands of Arrow Aviation’s technicians, installing the new Cobham EFIS displays and their associated components was just part of N401ES’s total makeover package.
"Other maintenance and upgrades included installation of new ERA auxiliary fuel tanks, aircraft NVG (night vision goggles) kit, emergency float kit, electrically heated windshields and increased generator capacity system," Evans said. "We also installed a new Lifeport EMS interior, and we repainted the aircraft."
"I think the installation of the Cobham EFIS system with HITS (highway in the sky) and synthetic vision greatly enhance the aircraft’s capabilities and safety," Nestor added.
"The EFIS provides simulated roll-steering to the flight director, allowing a more accurate coupled autopilot."
When asked how many hours Arrow Aviation had invested in the overall project, from inception through receiving the FAA STC, Evans answered with: "I’m not even going to go there... There was a lot of report writing and paperwork." There was so much that the project virtually lived up to the old adage: When the weight of the paperwork equals the weight of the aircraft, you will earn your STC. "Believe me," he said. "It’s pretty close."
Back in the Saddle Again
After FAA issued the STC this past May, North Slope Barrow pilots Hugh Patkotak and Robert Mercier along with technician Joe Lima departed with N401ES on its 4,000-mile trip from Louisiana to Alaska’s North Slope. Cobham Avionics’ western regional sales manager, Greg Schmidt accompanied the trio on the trip to provide familiarization training on the new glass displays.
Schmidt said that they flew nearly 40 hours to make the trip and the variety of terrain from sea level flatlands up to the Canadian Rockies gave the crew a chance to get familiar with many of the features found on the new Cobham EFIS system.
Because of the type of flying North Slope Borough SAR does, a critical component to ensuring pin-point position accuracy is the system’s WAAS Beta 3 GPS with five-megahertz data throughput. "It has five pieces of data come through the GPS every second," Schmidt said. "The typical WAAS Beta 1 GPSs only have one stream of data per second. There are a lot of benefits to this system — all built into one."
Schmidt said that the pilots took to the new displays very quickly. "You can tell them all about what it will do, but you don’t really understand it until it’s there in front of you," he said. "It truly reduces pilot workload exponentially for normal VFR and IFR operations."
Schmidt said that what really stood out to them was the system’s Hover Vector, HITS, and how easy the system is to use via the remote BUGS panel.
"Hover Vector was a big hit. When you are hovering you can instantly see your position along with any wind drift that is occurring," he said. "Hover Vector is displayed automatically on the PFD any time the aircraft is below 30 knots ground speed."
Benson said that while he’s impressed with all the various capabilities of the Cobham EFIS, the one display that he likes the best is the 3-D terrain display. "It’s probably going to be the one feature above all else that will be the greatest help," he said.
The system’s unique 3-D synthetic vision depicts the terrain as an intuitive, real-time ‘picture’ allowing the pilots to see the helicopter’s position in relation to its surroundings, regardless of darkness or weather conditions. The display also reduces instrument scanning and pilot fatigue by consolidating information from all primary flight instruments into one small area. The result is dramatically reduced pilot workload and overall safer aircraft operations.
Another of the features found in Cobham’s EFIS that is especially beneficial to North Slope’s operations is its night vision goggle compatibility. "It’s a big black hole up here in the wintertime. There’s little to define the landscape around here," Benson explained. "Night vision goggles are probably one of the most useful tools up here for us. With them we can spot a target 10 miles off."
"I have not flown with the NVG and the Cobham displays, but one of our guys has and I didn’t hear any complaints," he said. "We won’t get a real feel for them until winter hits."
Safety is a Priority
From its advanced Cobham EFIS to its fiber-optic gyros, extended range fuel tanks and host of other features, the nearly 30-year old N401ES is arguably the most capable Bell 412 in Alaska. But even with its kicked-up abilities, Benson emphasizes that safety is, above all, the number one priority. "This is the kind of environment that you cannot take a cowboy approach to anything," he cautioned. "If you do, somebody is going to get hurt. We’re not in the business of hurting people."
"I put a lot of responsibility on our PICs here to decide whether they are going to go or not," Benson said. "Even though our attitude is to always go, you have to keep things in perspective — the weather, the mission, the ability of the aircraft and crew."
"I remind my guys that they are flying out in their own means of rescue. If they have a problem they’ll have to wait for the guys to come in snow machines or four-wheelers to pick them up," he said.
As one would guess, consistent training is part of the North Slope’s safety culture. All the pilots rotate to FlightSafety every six months and they complement that with constant in-house training. "We have simulators for the fixed-wing here and we do quite a bit of flight training in our aircraft," Benson explained. "I do all the training in the helicopters and the King Air. There’s no theoretical stuff out here on the Slope — we go out and practice it in the real world."
As Good as it Gets
Benson said that although they haven’t experienced an Alaskan winter with N401ES, he’s confident that all the upgrades will solve their chronic mechanical problems and give them the high level of reliability and dispatchability that they need to serve the Borough’s residents.
In fact, North Slope is planning to send their other Bell 412, N402ES, to Arrow Aviation for its Cobham upgrade just about the time this story goes to print, and that they are seriously considering a similar upgrade for their King Air.
But Benson isn’t rushing things. "We want to get some cold weather experience with the installation and make sure it will work like we expect it to before we send the other helicopter down to Louisiana," he said.
While Benson and his entire team are really happy with the performance they’ve experienced with their ‘new’ 412 and its various upgrades, one part of the whole process has turned out to be quite beneficial, and it wasn’t part of the project. "Greg [Schmidt] did not have to do what he did — ride all the way from Arrow up to Barrow and then spend an extra week here training our guys," Benson said. "Had it not been for that, I don’t think we would be as far along as we are with our learning curve. What he did was immeasurable really. We greatly appreciate it. I think that’s why our attitude towards Cobham is so positive."
(NOTE: Before our sharp-eyed readers start dropping notes to the editor, the EFIS photo with the story has Chelton on the bezel. Chelton is now part of the Cobham Avionics group and these units do not reflect the name change.)
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