Workload reduced to make hands-off box
Northstar won permission to do things a little differently than what is listed in the FAA's Technical Standards Order C-129 Class A1 document. The crowning achievement of the 12-channel M3 GPS Approach — when flying a full approach procedure — can be summed up in two words: no holds. That is, the pilot does not have to place the automatic sequencing of fixes along the approach route on hold when making a procedure turn.
Northstar believes nonprecision approach procedures are simpler to execute with the M3 than with the approach-capable boxes that beat the Northstar to market. The result is a GPS receiver that guides the pilot around the procedure turn, down the final course, and through the missed approach procedure without any button pushing by the pilot. The entire approach, complete with holds and each leg of procedure turns, is programmed into the database. This feature alone exceeds the FAA's basic requirement of simply being able to fly a procedure turn.
Whether it be a DME arc or a nonprecision approach with a holding pattern for a procedure turn, the pilot literally follows the needle on a linked course deviation indicator. Aircraft owners who link the M3 Approach to an HSI will have to pay more for installation and will have slightly more knob twisting during an approach; the appropriate course needs to be set when using a horizontal situation indicator. With a left-right indicator, the pilot simply follows the needle without resetting the course.
Northstar says that its suggested list price prior to installation is $6,395, with an average retail price of $5,500. That does not include Northstar's offer of a $1,000 rebate to those trading in an old M1 model. The M2 and the Northstar GPS 600 can be upgraded to an M3 for less than $2,300.
The retail price is higher than those of some of its competitors, but Northstar says that the difference is offset by a simpler, and therefore less costly, installation. M3 Project Manager Steve Bennett claims that installation, especially after the dealers become familiar with it, will take about 20 hours of labor for a total cost of $1,000, or $500 less than what some of the other manufacturers are estimating. Bennett has since left Northstar for other pursuits. If you already have an M3 GPS, it can be upgraded to an M3 GPS Approach for free.
Why, you may ask, does a panel-mount GPS cost 10 times more than a handheld GPS? Three reasons: the receiver must be much more sophisticated to win certification, the navigation software is more complicated, and both must be certified to IFR standards. IFR certification, something handheld GPS receivers do not need, can take one or two years and is expensive. Additionally, handheld receivers are made in greater quantities, allowing economies in manufacturing.
For those wanting to link the unit to an HSI, there are additional costs. A switching relay to work with the HSI will cost an additional $1,000 in parts and labor. (Your aircraft may have a standalone CDI already TSO'd to work with a GPS, eliminating the need for the switching box.) A CDI is not included, but one made by Mid-Continent Instruments in Wichita includes the annunciator lights and sells for $620 to $695, depending on lighting, or that company can modify a few of the CDIs originally made for the Northstar loran.
Once installed, there is one final and continuing cost — the navigation database update. The unit ships with a current database, of course, and comes with an offer for one free update. To use the M3 Approach for nonprecision approaches, 28-day updates are required by the FAA. The subscription price is $700 a year for 13 updates. "The updates contain data from not only Jeppesen but the FAA as well — specifically private airports. No one else does that," Bennett said. Operating software is included with each database update, so users will always have the most up-to-date features available without having to send the unit back to the factory every few years. The update and the new operating software come on a PCMCIA card that inserts directly into the unit. To insert the card, the unit must be slid part way out of its mount.
Does that mean the M3 Approach will be easily upgradable when precision approaches using WAAS (Wide Area Augmentation System) become available? Sorry. At that time, the M3 Approach becomes your "nav two," Bennett said. It will become your backup navigation radio.
"WAAS won't be mainstream for 5 years," Bennett said. "C129 boxes are the only mainstream devices now. We didn't design it for a WAAS mod. The technologies available 5 years from now will be different. Displays and other things will be different. Five years is a long time in the electronics industry."
The M3 Approach does not have a moving map, although it is capable of driving one, such as the Argus 3000, costing about $3,000 ($2,600 discounted), or the IFR-approved Argus 5000, costing about $5,000 ($4,300 discounted). Look for the Northstar WAAS-capable box, to be built once the government has determined WAAS standards, to include a moving map.
While the unit has only a one-line display, it didn't seem as though any additional information was needed during a demonstration of nonprecision approaches. The 32-character display can be divided into two screens; approaches are typically flown with track error (TRK) information on one side and information such as groundspeed and distance (INFO) on the other. More lines of display might be nice to have when looking at typical airport information, such as runway length and radio frequencies, but the information is quickly scrolled at the twirl of a knob.
Speaking of airport information, the M3 GPS Approach performs a little trick that pilots new to GPS will appreciate. Let's say you wake up your M3 at Cleveland and are unfamiliar with the airport. The M3, because it knows where it is — and senses that it is not moving — will call up a database of radio frequencies needed to get you under way. (Several of Northstar's competitors have this feature.) Those who have the Northstar C1 transceiver will find those frequencies already tuned and waiting. No more scrambling for ATIS, clearance, ground, and tower frequencies. En route, this same feature — called SmartComm — will look up weather and air traffic control frequencies based on your location.
Northstar engineers intentionally designed the M3 Approach to look like the earliest of Northstar models so that upgrading customers would not have to relearn the box. There are still two control knobs — one on the left called primary, and one on the right called secondary. Each knob has a smaller concentric knob.
To call up an approach, select APCH with the large primary knob and enter the airport identifier, using the smaller primary knob, either by scrolling through a list or by selecting CRSR and entering the identifier character by character. If necessary, turn the large secondary knob (on the right side) all the way to the left to display Level 1. (Level 1 is the first stage of setting up the approach and includes selection of the airport and the approach.) The destination airport will pop up on the primary (left) display. Also shown will be the estimated time of arrival. If necessary, you may adjust the time with the small secondary knob (on the right side of the radio). This allows the M3 to tell you if the GPS self-checking function (Receiver Autonomous Integrity Monitoring) will be unavailable when you arrive. That is, it will make sure that enough satellites will be in position for a high level of accuracy during your approach. Press ACK to accept the destination and arrival information.
With the large knob on the left still set to APCH, turn the small primary knob to display the approach name. Now turn the small knob on the right to display the entry point, such as an intersection — or, more likely, vectors to final. Press D for direct and ACK to start the approach. This last step may be left until the approach is needed while the box operates in other modes for en route navigation. In other words, you can set up the approach well before the estimated time of arrival.
When using a CDI, the Northstar guides the aircraft outbound from the final approach fix, waits patiently for the pilot to complete the procedure turn, and senses when the distance to the final approach fix is decreasing. When that happens, the M3 automatically resets to the inbound course; when the final approach fix is passed, it sequences to the missed approach point. Sensitivity will gradually change from one mile for a full-scale deflection outside the final approach fix to three-tenths of a mile from the final approach fix inbound.
Once at the missed approach point, you can either land or press a flashing white button to execute the missed approach. After acknowledging that you want to fly the missed approach procedure and that you are aware of the altitude requirements, the M3 leads you by the hand through the missed approach procedure. Don't worry about intercepting radials or finding holding patterns located on nearby DME arcs; just follow the needle.
Elimination of the procedural hold during an approach was one of the primary "wins" from discussions with the FAA. "We don't have a hold mode. That is the fundamental difference. We don't even have the concept of a hold mode," Bennett said. "The majority of things were approved," Bennett added. "We had the hardest time on things that had nothing to do with approaches. We had to redesign some of our features that had been in the design since the M1 loran. For example, when you get to the end of the alphabet, there is a physical stop [on the M1]. The FAA said that had to be a continually scrolling alphabet."
The FAA, of course, is interested in standardization. When a pilot gets out of one aircraft and into another, it should not be necessary to relearn the GPS navigation radio. FAA inspectors in different parts of the country appear to have different ideas of what that standard should be, Bennett said. However, it would appear that the fledgling GPS industry is not ready for a standardized box. The best method is still being determined, and customers are voting with their dollars. Northstar officials consider the way they handle a nonprecision approach, compared to that of other brands, to be a competitive advantage. Because of its novel design Northstar's M3 GPS Approach was required to pass muster before a special FAA inspection team.
Does Northstar have a better mousetrap? It would appear so, if simplicity of operation is the primary criterion.
For more information, contact Northstar Technologies, 30 Sudbury Road, Acton, Massachusetts 01720; telephone 800/ 628-4487 or 508/897-6600.
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