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Here’s a familiar scenario: An owner steps up to a twin or a high-performance single that’s equipped with an older radar system. Unwilling to spend the money and effort to fix it or replace it, they pay to have the system removed. Sadly, many of these owners don’t recognize the benefits of ship’s radar.
The decision to fly without radar—particularly at high altitudes—might seem easy to pilots who grew up with satellite-delivered cockpit weather. Depending on your view of weather avoidance, or tactical penetration, real-time ship’s radar might be imperative for your mission.
There’s no question that weather radar maintenance and upgrades can be pricey. We're talking the potential for several thousands of dollars for repair and tens of thousands for upgrade. On the other hand, ship’s radar can expand the mission. In volatile weather, there’s a reason why controllers ask if you have onboard weather radar.
Where radar upgrades were once in decline, the ability to overlay weather radar on GPS navigators, multi function display systems and integrated glass cockpits has jump-started the radar upgrade market. In our view, radar design and technology that was once only available to the jet market is making radar system upgrades more convincing for lower-end applications.
For those that are unfamiliar with ship’s weather radar, here’s a basic review.
Pulsed radar locates targets (precipitation or ground clutter) by transmitting a microwave pulse beam that reflects off the precipitation and back to the radar receiver as a return; this is often called an echo. The microwave pulses are focused and radiated by the system’s antenna (often called a dish) that’s located in the nose of twins or enclosed in a wing pod on singles. This structural enclosure is called a radome. The same antenna is used for both transmitting and receiving.
The returned signal is processed and displayed on either a dedicated radar display, or as a remote input to an MFD. The MFD option has been the saving grace for a somewhat stagnant GA radar market because the color MFD has greatly enhanced the display and effective usefulness of aging systems. If you’ve made the switch from a monochrome radar display to a VGA display you understand the benefits and can appreciate the enhanced view.
Think of the radar beam that’s transmitted from the aircraft as a spotlight. As the beam travels farther it gets wider, limiting performance. The smaller the antenna, the wider the radar beam and the more its energy is dispersed over each mile it travels away from the aircraft. As a rule, the larger the antenna, the better the performance. Smaller twins and singles might be limited to radar systems with 10-inch antennas (10-degree beam) because the aircraft’s nose or wing-mounted radome simply can’t accommodate a larger antenna. Consider that an airliner might have a 30-inch radar antenna.
It’s all about beam width. When scanning longer distances with a smaller antenna, precipitation can’t fill the entire beam width, so a real-deal Level-5 might be displayed as something much smaller. As a result, you’ll need to fly closer to the storm to obtain a more accurate return.
The digital RDR2000 has an earned reputation for both reliability and performance. We searched the used market and discovered that used ART2000 units (the ART2000 is the main radar system less a display) demand well over $10,000. According to seasoned radar repair shops, including Fieldtech Avionics and Duncan Avionics, the RDR2000 is one of the most demanded radar systems for piston singles, twins and even light turbine applications. There's also the high-powered RDR2100 that's appropriate for jets.
The vertical profile feature provides just that—a vertical picture of a pilot-selected cross-section of a storm. The RDR2000 has a 270 nautical mile range, paints in four colors and has 4.0 kW of power output. The higher-powered RDR2100 has 6.0 kW of power that can scan out to 320 nautical miles.
The RDR2000-series has long been a part of the Bendix King product line and is a major optional interface for the company's new KSN770 retrofit GPS navigator. It's still used by some aircraft manufacturers as standard equipment, including Pilatus, on the PC12NG.
The ART2000/2100 was originally designed to display on the IN-182 dedicated radar display (no longer available). You can, however, interface the system with Avidyne's EX600 MFD when equipped with the proper radar interface kit. This kit comes with a premanufactured radar interface cable that connects the MFD with the radar. Avidyne says the future IFD540 GPS navigator will be compatible with the ART2000 system.
A new ART2000 has a list price of nearly $23,000. We don't see anything wrong with buying a used ART2000, as long as you buy it from a reputable source that has radar testing and repair capability. It should include a warranty and appropriate airworthiness paperwork.
Flash back to the year 2000 when Garmin purchased the rights to the King KWX56 radar (a system that was supported by the late Narco Avionics). It was then that we realized Garmin was serious about stepping into the heavier aircraft market.
The KWX56 was a case study for how to make an older radar new—and more reliable. It was the magnetron that Garmin focused on the most, since this component is notoriously the most expensive and problematic component on a ship's radar.
Garmin also reworked the dish array into a flat plate antenna, which provided a sizable gain in transmit power. How much power? The GWX68 is spec'd at 6500 watts—nearly twice that of vintage systems. More power improves range and resolution not only at the higher end but also at the lower end of the spectrum. Where other systems struggle at painting reliable returns at close distance, the GWX68 excels and has a 2.5-mile scan range. This means better awareness on an approach and when trying to weave a path around cells.
As you might expect from a higher-end radar (and perhaps to mimick Honeywell's RDR2000) there's also a vertical mode that scans a 60-degree vertical arc. Since Honeywell calls this vertical profile, Garmin calls it vertical scanning. There's even a high-end function borrowed from jet radar systems, called sector scanning. With sector scan, the system can look out at angles up to 90 degrees, even when manuevering. Again, this is helpful when manuevering in close proximity to storms. For better awareness at greater distances, the target alert feature can sniff out stronger returns in better detail.
The recently-introduced GWX70 picks up where the GWX68 left off (both are available in Garmin's line-up) and utlizes a solid-state transmitter. This transmitter eliminates the magnetron while also bringing turbulence-sniffing Doppler capability to the system.
You would think that a solid-state transmitter increases the transmit power of the radar, but that's not the case. Consider that the GWX68 has 6500 watts of power through its high-power magnetron, but the solid-state GXW70 only has 40 watts of power, while still providing better range and reducing ground clutter.
The other enhancement comes from a new processor that utlizes digital signal processing technology (DSP). Garmin says that by using a DSP processor it's able to gain better control of the radar's pulse width and signal output. DSP, says Garmin, overcomes the challenge of obtaining an accurate picture at longer ranges. While a magnetron-powered radar pumps out huge amounts of power, the clarity of the resulting long-range returns are compromised—or in some cases, missed entirely.
Doppler capability requires a larger antenna (either the 12, 14 or 18-inch models). While the GWX70 is offered in a 10-inch configuration and can bolt into an existing Garmin GWX68 installation, the Doppler model will be off limits to aircraft with a smaller radome. The GWX70 with a 10-inch antenna starts at $21,000—the same price as the magnetron-equipped GWX68.
No matter which system you chose, you’ll want to be certain the existing radome is up to the task. A radome lives a hard life and can ultimately contribute to poor radar performance. The surface paint and primer often erodes, peels or cracks. Take a look at the nose on a radar-equipped aircraft and you’ll see the damaging effects of rain, high velocity airflow, grit and other contaminants.
It’s not a simple task to refinish a radome surface (spraying the surface with a can of spray paint isn’t the correct approach). The typical radome is made of a honeycomb core, layered fore and aft with resin-impregnated fiberglass facings. It's generally not enough to rattle-can a deteriorated radome. It might make it look better, but don't expect gains in performance.
Before sending a radome out for professional evaluation, you might conduct a crude test of your own. One is the coin test to evaluate the bonding of the lamination. Take the thin edge of a larger coin and tap various areas of the radome while listening for undesirable dull thunking sounds. Instead, a firm click is what you generally want to hear.
You can also remove the radome for a visual inspection (this could be a two-person job on some aircraft). Hold the radome in the bright sunlight and look carefully at the honeycomb for debonding, cracks and puncture holes. When putting the radome back on, be sure to reconnect the glideslope antenna that's often attached to the inside, which is the case on smaller Beech twins.
Finally, whatever you do, don't operate the radar on the ground (in any mode other than test and standby) anywhere near major structures and humans unless you want to toast the magnetron and the human.
When getting proposals for avionics that can accomodate radar overlay, it's worth it to at least get a quote for a new or used radar upgrade. Your shop will know which systems are compatible with the gear being installed and which systems will fit the existing radome.
The physical radar installation isn't necessarily complex but could require sizable electrical interfacing, especially when tying into an AHARS system for roll and pitch stabilization. Garmin's GWX systems are interconnected via ethernet databus and will require healthy amounts of configuration, set-up and flight testing.
A new radar installation won't be cheap, but it could be the better choice than sinking money into older systems that are likely to fail again. Better yet, it could expand your mission while complimenting an onboard satellite weather and lightning detection system.
Transitioning to your first aircraft that has ice protection equipment beyond a heated pitot tube is a big step for a pilot. Having a full complement of ice protection usually gives pilots warm fuzzy feelings about being able to complete more trips and handle any ice related problems that arise. Unfortunately, the current regulations and guidance addressing icing can be just as complex as dealing with the nuances of inflight icing encounters.
Case in point is the FAA’s recently proposed Airworthiness Directive for 300 and 400 series twin Cessnas produced in the early 1970s and before (Federal Register Docket FAA-2011-0562). The AD would prohibit all covered aircraft from flight into icing conditions because these aircraft were not required to demonstrate adequate ice protection performance when produced. Performance wasn’t demonstrated because no certification basis existed under 14 CFR Part 23 when they were built.
And that’s the problem. Certification standards for flight into known icing (FIKI) have changed drastically over the years, as has the very definition of what even constitutes icing conditions, and it’s always difficult to hit a moving target. Let’s get to the bottom of what it takes to fly in ice in the current regulatory environment.
If you fly a relatively new aircraft that is FIKI certified, you should have some confidence in knowing that modern icing certification is a rigorous process which involves demonstrating safe flight in specific icing conditions, known in the regs as Appendix C Icing Conditions. However, it wasn’t always this way. This is where much of the “is it?” or “isn’t it?” confusion arises for pilots flying many older aircraft.
It would be great if every aircraft flying today adhered to the same type certification standards, but that’s not the case by a long shot. Every individual type was required to comply with the standards in place on the date of its certification by the FAA. That certification basis is listed in the aircraft’s Type Certificate Data Sheet (TCDS). This gives you the key to determining the ice protection standards that were required for certification.
Prior to 1974, there effectively weren’t any FAA standards for general aviation icing certification. During this period, aircraft were not specifically allowed or disallowed from flight into icing conditions by the FAA, and any published limitations were made by the manufacturer. In 1974, certification standards were added for general aviation aircraft that parallel transport category ice certification.
For many older ice-flying aircraft, there have been thousands of hours flown in real-world icing conditions, and the word on the street from pilot groups, while probably not as rigorous as current FAA certification standards, is certainly more thorough than what most test flights can accomplish. Therefore, it is beneficial to investigate the certification standards for your aircraft as a way of predicting future FAA interest in the icing capabilities of your aircraft type, such as with the proposed twin Cessna AD.
One of the first questions a pilot will ask when transitioning to an aircraft with ice protection is about how well it carries ice. This is a reasonable and insightful question to ask. Every aircraft carries ice differently, with the variability coming from the wing shape, type of ice protection being used, type of ice encountered and a variety of other factors. In my experience one of the biggest factors is the power to weight ratio. After all, given enough horsepower you can make an ice-laden barn fly.
Back in my freight dog days, I primarily flew the Cessna Caravan, a great flying airplane with a bit of a bad reputation (partially deserved, partially undeserved) when it came to ice. The Caravan certainly had ramp presence. It was big. Even with that 675 shp engine hanging off the nose, it was actually underpowered. That engine had to pull an aircraft that maxed out at 8,550lbs with the cargo pod. This yields a power loading ratio of 12.67 pounds per horsepower.
An aircraft’s ability to climb is directly related to power in excess of that required to maintain level flight and is of critical importance when dealing with an icing encounter. The Caravan was a deceptively easy plane to fly, but its lack of excess power is the root cause of its icing reputation. The Caravan could certainly carry a load of ice, but because of the lack of available power to climb, the pilot simply wasn’t permitted as much time to form a plan to deal with an icing encounter as might have been allowed in another aircraft type.
Keep in mind that the power being considered here is the available horsepower, which decreases with altitude for normally aspirated aircraft. Additionally, remember that ice is heavy, and that the bigger the physical size of your aircraft, the more unprotected surfaces will become contaminated and the quicker weight will build due to ice accumulation. So if your aircraft is already at its maximum weight (in the absence of an ice weight limitation), picking up ice could mean you have become over gross weight while aerodynamically compromised. That’s not a good combination.
The current standards for ice certification for both normal and transport category aircraft are limited to the scientifically described icing conditions documented in Appendix C of FAR Part 25. A challenge for pilots flying aircraft certified under that section is being able to correlate those scientific standards with what they’re seeing out- side and identifying conditions that exceed those standards. Specifically, supercooled large droplet ice (SLD), freezing rain and freezing drizzle, all of which cause ice accumulations aft of protected surfaces, are outside of the standards for any aircraft.
For a long time, “known icing conditions” were only defined by case law and legal interpretations. In 2006 an FAA interpretation attempted to define it as temperatures at or below freezing in visible moisture, which effectively meant any clouds in the winter. In 2009 they backpedaled into a surprisingly common-sense definition that known icing conditions exist when a reasonable and prudent pilot would know of them based on all the weather information available at that time.
Now the responsibility is on the pilot to become educated into understanding what causes ice, self-certify that a proposed flight will not exceed his aircraft’s icing capabilities and make contingency plans for unforecast icing encounters. For aircraft lacking a FIKI certification, that means steering clear of all forecast ice. For known-ice aircraft, that means steering clear of all forecast ice that exceeds limitations on the aircraft type, or common sense.
The graphical weather products that are available today make planning to avoid ice much easier than even a few years ago. AIRMETs and SIGMETs, combined with freezing level graphics and pilot reports, supplemented with the Current/Forecast Icing Potential graphics, give pilots many valuable tools to use. Part of the challenge of forecasting ice is its fickle nature—as air masses evolve, icing conditions in an area can change significantly over a short period of time. Therefore, on an IFR winter flight that’s expected to be clear of ice, always pay attention to conditions that don’t seem to be supporting your preflight analysis.
FAA certification of an aircraft for flight in icing conditions encourages the already common misconception that it’s safe to fly in icing conditions and that pilots can relax. This is an important point that can’t be overstressed. Just because an aircraft is granted known icing certification by the FAA, even using today’s more stringent standards, does not constitute an authorization to fly in any conditions. In fact, for most aircraft and GA aircraft in particular, FIKI certification should be viewed by the pilot as merely an ability to transit brief icing encounters, not to fly through ice for hours.
Like so much in aviation, we know a lot more about ice today than we did a few years back, but we’re still a long way from knowing all there is to know. Having a defined standard for ice protection is certainly useful, but it is not sufficient. We’re always reading about aircraft that have met all?the modern Part 25, Appendix C, certification standards finding out exactly how much ice is too much for their aircraft type, and paying dearly for the discovery. Unfortunately, Mother Nature doesn’t always adhere to the Appendix C definition of ice.
Consider one of the findings made by the NTSB after the 1994 ATR-72 crash in Roselawn, Indiana:
The 14 CFR Part 25, Appendix C, envelope is limited and does not include conditions of freezing drizzle or freezing rain; thus, the current process by which aircraft are certified using the Appendix C icing envelope is inadequate and does not require manufacturers to sufficiently demonstrate the airplane’s capabilities in all the possible icing conditions that can, and do, occur in nature.
I suspect we’ll never be able to demonstrate capabilities in all possible icing conditions that Mother Nature can throw at us. Therefore, safety in icing conditions should be primarily a factor of pilot education, respect for the pilot’s and the aircraft’s limitations and the rarest and most valuable asset there is: common sense.
A version of this article appeared in the January 2013 issue of IFR Magazine.
For more than a year, Continental Motors has been experimenting with a new flight training center based in an upscale mall in Spanish Fort, Alabama. AVweb recently visited the center and interviewed Gloria Liu for a briefing on the training works.
When I was researching last week’s story on aircraft refurb business, I heard all kinds of comments, but everyone—well, almost everyone—agreed that new aircraft prices have made flying unreachable for all but the very wealthy. When someone of the stature of Jack Pelton flatout calls airplane prices exorbitant, you have a five-alarm fire.
And by the way, no one I talked to last week thought that the manufacturers can do much in the short term about escalating prices if they hope to remain solvent. If you believe that cutting prices would expand the market, they would have to discount so much that no manufacturer could survive long enough to enjoy the higher volume.
So we have this groundswell of refurb activity and it looks like it definitely has legs. There’s an ocean of low-cost, high-value airframes out there that basically perform as well as modern aircraft do. They go as fast, carry as much—and sometimes carry more given how portly modern airplanes have become—and burn the same amount of fuel. The only exceptions are the diesel conversions and that’s where Redbird is going with its Redhawk project. That’s still a tiny market.
So since these older airframes can be readily upgraded to nearly state-of-the-art status and perform for half the price of new, that’s a good thing, right? Evidently, the market thinks so, because refurb is hot. But is there a downside? Does an expanding refurb market potentially damage the development of new GA aircraft? John Armstrong, who’s had success putting together shared arrangements for access to new Diamond aircraft, thinks so. He told me the longer older airframes remain in the fleet—fixed up or not—the longer it will take to replace them with safer, newer aircraft that he likes to call “magic carpets.”
Basically, the DiamondShare program is a multiple access arrangement that has, at its core, a buyer who takes delivery on a new DA40XLS. DiamondShare then does the legwork to recruit “members” who, for a fixed payment, share access to the aircraft at a price typically around $1000 a month. DiamondShare offers tax and insurance support, training and other services. It’s not a partnership, nor is it a club. Armstrong describes the program as leveraging the aircraft’s excess capacity—basically potential hours of availability the owner isn’t using—to offset costs the owner would otherwise bear entirely on his own. “Would you pay $1000 a month to have access to this magic carpet?” comes the sales pitch from Armstrong. (You pay for your own gas.)
The answer for me might very well be yes, if I had compelling need for a DA42 with a glass panel. But since I can’t justify that kind of money for just boring holes in the sky and it’s not practical for regular business travel, I have a position in CubShare instead. But when I used one of several Mooneys for regular business travel, the grand a month was about the cost, on an annualized basis. But that included the gas. Nonetheless, the value was there, in my view, and it would be for the Diamond, too.
But I’m skeptical that any amount of refurb activity would impact the likelihood of buyers opting for new instead. Buyers of new airplanes have to suppress the gag reflex when they see a $400,000 sticker and/or be creative enough to instantly realize how they can leverage that number to make it affordable while calculating how much depreciation they’re willing to eat. I think buyers of new piston airplanes—and there aren’t but about 500 of them a year in the U.S.—look at this from the top down while those of us seeing the value in used airplanes look from the bottom up. How high are we willing to go to hit the magic price/value point? I suspect it’s in the $70,000 to $100,000 range, which is where a lot of used aircraft transactions settle. And that’s why nicely executed refurbs up to, say, $150,000, are likely to be increasingly attractive.
Do buyers care that the airframe may in fact be 30 years old? Some do, says Premier Aircraft’s Jeff Owen. But for many, not enough to spend five or six times as much for an airplane that has only marginal additional capability and maybe not even that if the refurb has a nice Aspen glass panel. Yes, the OEMs may lose a few sales to spruced up recent models, more so in the TAA-type aircraft than a tarted up mid-1980s Saratoga. But they’ll live and die not selling against refurbs, but finding those lucky 500 who can write a check for a half mil.
In this exclusive AVweb podcast, AOPA's newly installed president, Mark Baker, says the association will adopt an airport-centric means of promoting aviation and will concentrate on a regional strategy to reach the membership. Baker also told AVweb that all of the association's activities — from fund raising to member support to starting new business lines — will be under review during the coming months.
On the morning of September 12, 2013, Jonathan Trappe ascended from a field in Caribou, Maine, in an attempt to be the first pilot to fly a cluster balloon system across the Atlantic. Twelve hours later, he landed in Newfoundland.
Many round-the-world pilots are in a hurry to get the trip done, but Calle Hedberg of Capetown, South Africa is taking a different route. He has eight months to do the trip in his kit-built Ravin 500, and he plans to savor every moment. AVweb's Russ Niles flew with him after he got a float endorsement in Kelowna, British Columbia.
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