Limits of See and Avoid

On November 16, 2000, at 1548 eastern standard time, a U.S. Air Force F-16CG, operated by the 347th Wing, Air Combat Command, collided in mid air with a Cessna 172, N73829, near Bradenton, Florida. The F-16, based at Moody Air Force Base (AFB), Valdosta, Georgia, was on a low-altitude training mission. The Cessna 172, registered to Crystal Aero Group, was operating as a 14 CFR Part 91 personal flight. The airline transport (ATP)-rated Cessna pilot was killed. The F-16 pilot, who held a commercial pilot's certificate, ejected from the airplane and sustained minor injuries. Visual meteorological conditions prevailed at the time of the accident.

This accident offers a dramatic illustration of the risks of fast-moving military aircraft operating in the vicinity of slow-moving GA aircraft. And as you'll see, the accident also illustrates that military personnel are human: They can and do make mistakes. Safely sharing airspace with military aircraft requires an understanding of regulatory and non-regulatory airspace, including special use and other airspace. It's also important to recognize the limits of the "see and avoid" collision avoidance technique. Last but not least, knowing where military aircraft are scheduled to be operating can help you avoid coming into close proximity with fast moving hardware.

Rules or No Rules?

The national airspace system is divided into two basic categories: Regulatory and Non-regulatory. Regulatory includes Class A, B, C, D, and E (aka Controlled Airspace and defined in 14 CFR 71) as well as Restricted and Prohibited areas (aka Special Use Airspace and defined in 14 CFR 73). As implied by its name, regulatory airspace has specific regulations that define who can enter and operate in that airspace. Break those regulations and you'll find yourself in trouble with the FAA.

Non-regulatory airspace includes Military Operation Areas (MOAs) as well as Warning, Alert, and Controlled Firing areas and these are defined in FAA order JO 7400.8: Special Use Airspace, which describes the location, dimensions, times of use, and identifies the controlling agency. There are no specific regulations restricting flight into these areas, other than those for VFR cloud clearance and visibility. There are some common sense operating procedures that pilots should follow and failing to use those procedures may get you some unwanted adventure, or worse.

Mysterious MTRs

The above-cited accident involved, at least peripherally, a Military Training Route (MTR), a type of non-regulatory airspace that has been given the innocuous classification of other airspace. MTRs are depicted on VFR charts as subtle (some say nearly invisible) charcoal lines with a two-character prefix followed by a three or four digit number. Flights on MTRs with an IF prefix are conducted under IFR while those with a VF are usually conducted under VFR. A three digit number following the prefix indicates the military aircraft should be operating above 1500' AGL and, to the maximum extent possible, under IFR. A four digit number indicates the aircraft may be operating below 1500' AGL. In general, you can expect military aircraft on these routes will be operating in excess of 250 knots. They may be operating close to the surface or they may be at higher altitudes during descent to or climb out from the route.

Other that what's encoded in the MTR identifier, there is precious little information available to the average pilot who does not possess a current copy of the DoD's flight information publication Area Planning: Military Training Routes: North and South America, also known as the AP/1B. About the size of a small phone book, the AP/1B is published every 56 days and defines each MTR's location, hours of operation, route description, operating procedures (VMC or IMC), route width, and entry/exit points. Many routes have specific restrictions and can only be flown by certain types of military aircraft, but I know of no way for civilian pilots to get their hands on a current copy of AP/1B.

The flight lead stated that the two F-16s were assigned a block altitude of between 25,000 feet and 26,000 feet en route to the entry point of visual military training route (MRT) VR-1098. As the flight approached the SRQ area, Miami Air Route Traffic Control Center (ARTCC) cleared the F-16s to descend to 13,000 feet. At 1543:39, the Miami ARTCC controller instructed the flight lead to contact Tampa Terminal Radar Approach Control (TRACON) controllers. The flight lead was not successful (because he was given an incorrect frequency), and he reestablished contact with Miami ARTCC and canceled IFR. Miami ARTCC advised him of traffic at 10,000 feet, which was acquired on radar. The controller accepted the cancellation and asked the pilot if he wished to continue receiving radar traffic advisory services. The flight lead declined. According to the air traffic control (ATC) transcripts, the controller then stated, "radar service terminated, squawk VFR [transponder code 1200], frequency change approved, but before you go you have traffic ten o'clock about 15 miles northwest bound, a Beech 1900 at ten thousand [feet]." The flight then began a VFR descent to enter VR-1098.

See and Avoid

In addition to the laissez-faire character of special use airspace is the fact that most traffic collision avoidance is accomplished with the see and avoid technique. When a mid-air accident occurs, the NTSB always states that the cause of a mid-air was the pilots' failure to maintain adequate lookout for other traffic.

There have been several studies that attempted to determine how pilots scan for traffic, what a good scan is and what a bad scan is, how head-down time (due to complex avionics and pretty colored moving maps) affects the scan. Traffic collision avoidance hardware (whether installed or portable) can be a help and I always fly with a Zaon PCAS affixed above the instrument glare shield. The problem is that in spite of training, admonishments, and collision avoidance hardware, mid-air collisions continue to occur at about the same rate and most occur in visual conditions.

Speed can Kill

When quizzing pilots about 14 CFR 91.117 (airspeed limits) during a flight review, I hear comments that these regulations don't apply because they fly slow moving aircraft. I usually counter that it's important to know how fast the other guy might be going and then add that there is an escape clause which can result in the other guy going even faster (emphasis added):

(d) If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.

The minimum recommended cruising speed for an F-16 below 10,000 feet is 300 knots, but this flight of two was going even faster (emphasis added):

The F-16 flight entered the top of the class B airspace about 380 knots airspeed and left the airspace at 6,000 feet about a minute later at 360 knots. Speeds of up to 450 knots were noted during the descent. The airspace between Tampa class B airspace and Sarasota class C airspace is Class E airspace, with a lower floor at 700 feet. About 30 seconds after leaving the Tampa class B airspace, the flight entered the Sarasota class C airspace at 380 knots. The flight remained in the Sarasota class C airspace where the midair collision took place. The flight lead's speed remained above 300 knots until the accident F-16's collision with the Cessna. 

A Cessna 172 cruises between 110 to 120 knots, but a normal climb speed is around 80 knots. Needless to say the closure rate between the two accident aircraft was very rapid with just over 20 seconds between the time ATC received a conflict alert and the impact.

A review of altitude data and ground track data (and airspace boundaries) determined that Tampa TRACON's intruder conflict detection software noted a conflict between the flight lead and the Cessna, and generated an aural conflict alert in the TRACON facility at 1547:39 that continued until 1548:03.

Hazardous Training

It's interesting to note that training activities figure prominently in this accident. The flight of F-16s were training and the Tampa TRACON controller was receiving instruction from another controller.

After continuing to descend, the flight lead looked back to the left and observed the accident F-16 slightly below him at the 7 o' clock position and about 4,000 feet to 5,000 feet behind him. The flight lead also observed a white, high-wing white airplane (the Cessna) in a 30 to 45-degree right turn. The Cessna and the accident F-16 collided in a left-to-left impact at the flight lead's 10 o' clock position, he stated. After the collision, the flight lead observed vaporizing fuel on the F-16's right side. The flight lead did not see the Cessna. The flight lead called the accident pilot and stated, "it appears you have had a mid air and are streaming fuel." There was no response. 

The Cessna pilot had departed Sarasota-Bradenton, was inside class C airspace, and was in communication with Tampa approach.

The Miami ARTCC controller contacted Tampa TRACON at 15:47:55 and asked Tampa TRACON for the flight lead's altitude because he had lost radar contact with the lead F-16 (only the flight lead had his transponder activated because formation flights are handled as a single aircraft by ATC). Tampa TRACON replied at 20:48:00, stating "ahh hang on I see him down at two thousand." At 15:48:09, Tampa TRACON informed N73829 that he had traffic off his left side at 2,000 feet. N73829 did not respond.

The biggest single factor in this accident may have been that collision occurred inside Class C airspace where the Cessna pilot least expected encountering fast moving fighters because the F-16s were off course by several miles. The lead pilot may have thought he was at the entry point for VR1098, but he was mistaken.

Lockheed Martin examined the download data from the crash survivable flight data recorder (CSFDR), the SDR, data printouts from the general avionics computer (GAC), the global positioning system (GPS), the inertia navigation system (INS) and the AVTR tapes from the flight lead's airplane. Lockheed Martin's examination report stated that M Aero stated that GPS "was removed from the navigation solution at some time prior to the midair. It cannot be determined from the data why the GPS was removed from the navigation solution." The report added: "A position error of approximately 9-11 nm was entered into the navigation system at some time on the mishap flight prior to the video recording. It can not be determined from the data what caused this position error."

Avoiding Military Activity

There is no regulation that prevents you from operating in or around an MOA or MTR, but the conventional wisdom is to avoid these areas when they are active. If you must operate in or around these areas, then by all means get flight following from ATC. This accident illustrates that ATC traffic advisories are no guarantee that you'll be safe, but you want as much help as you can get.

To determine if an area is scheduled for use, contact Flight Service before you fly or talk the controlling agency. The FAA's VFR charts require that you first look up the identifier for the area you're interested in, then look on the edge of your chart to find information about times of use, altitudes, and the relevant radio frequencies. It would be a heck of a lot simpler if they just put that information next the depiction of the area, but they don't.

You can also reference this web site to get a graphical representation of regulatory and non-regulatory airspace, though there's a disclaimer that the most up-to-date information is only available through Flight Service.

The conventional wisdom I've heard from fighter pilots is that best strategy for avoiding an imminent collision with a fast moving military aircraft is descend. The fighter aircraft is likely going to climb to convert their fast airspeed into altitude, so you're best bet may to descend rather that turn away.

If you think military pilots can see you on radar and will avoid you, think again. They are focused on their training mission and don't have a lot of extra time to look for you. If you think military pilots are so highly-trained that they never make mistakes or errors in judgement, read the NTSB's probable cause (emphasis added).

The National Transportation Safety Board determines the probable cause(s) of this accident as follows: the failure of the F-16 flight lead pilot and F-16 accident pilot to maintain an adequate visual lookout while maneuvering. Factors contributing to the accident were: the F-16 flight lead pilot’s decision to discontinue radar traffic advisory service, the F-16 flight lead pilot’s failure to identify a position error in his aircraft’s navigational system, the F-16 pilots subsequent inadvertent entry into class C airspace without establishing and maintaining required communications with air traffic control (ATC); and ATC’s lack of awareness that there was more than one F-16 aircraft in the formation flight, which reduced the ATC controllers ability to detect and resolve the conflict that resulted in the collision.

And if you think you're Super Pilot, you can operate in these areas whenever you want, and that you'll be able to see a flight of two fighter jets operating close to the ground at high speed, well good luck to you. You're going to need it.

The Big Sky

On August 8, 2009, at 11:53 a.m. EDT, a Eurocopter AS 350 BA (N401LH) operated by Liberty Helicopters and a Piper PA-32R- 300 (N71MC) operated by a private pilot, collided in midair over the Hudson River near Hoboken, New Jersey. The certificated commercial pilot and five passengers onboard the helicopter were killed. The certificated private pilot and two passengers onboard the airplane were also killed. Visual meteorological conditions prevailed and no flight plans were filed for either flight. The local sightseeing helicopter flight was conducted under the provisions of 14 Code of Federal Regulations Part 136. The personal airplane flight was conducted under the provisions of 14 Code of Federal Regulations Part 91.

Following this very prominent midair collision, the media have been talking about procedures, policies, and regulations with which most reporters have little experience or expertise. This is nothing new. Every time I read a news story on a topic about which I'm not familiar, I wonder how accurate that story really is. But I digress ...

One news report seemed to imply that the pilot of the Piper (being a private plane) was at fault because it had run into the Eurocopter. The author of another story focused on the shocking fact that aircraft operating in the thin sliver of airspace over the Hudson River do so without talking to air traffic control and without a flight plan. Other reports tried to compare and contrast the water ditching of a US Airways Airbus with this accident. This compels me to comment on what is known about this accident, provide a pilot's perspective on operating in airspace that has little or no ATC intervention, and talk about just how well the see-and-avoid approach to preventing midair collisions really works. I'll attempt to address these issues so that non-pilots can develop a better understanding of just what pilots of smaller aircraft who fly at lower altitudes have to deal with on a regular basis.

Apples and Oranges
First off, the only thing this midair accident has in common with the ditching of US Airways Flight 1549 is that in both cases, the aircraft ended up in the Hudson River. The US Airways accident involved a bird strike (which I guess is kind of like a midair collision) that resulted in a loss of power to both engines: The Airbus was still be flyable, it just didn't have any thrust to keep it from losing altitude. The fact that the plane was still flyable, combined with the skilled flight crew and a lot of luck, resulted in an amazingly successful water ditching. In contrast, the midair collision between the Piper and the Eurocopter caused catastrophic damage, both aircraft departed controlled flight, and the impact with the water was not survivable. The only thing these two accidents had in common was their location.

ATC's Role
The Piper departed Teterboro Airport and was, in fact, communicating with the tower controller until he was over the Hudson, when he was handed off to the Newark control tower. Talking to an airport's tower controller is mandatory when an aircraft is within that airport's airspace. In these situations, ATC will point out other potentially conflicting air traffic, but this is done on a workload permitting basis. Here's just a bit of what the Aeronautical Information Manual has to say on the subject:

4-1-15. Radar Traffic Information Service

This is a service provided by radar ATC facilities. Pilots receiving this service are advised of any radar target observed on the radar display which may be in such proximity to the position of their aircraft or its intended route of flight that it warrants their attention. This service is not intended to relieve the pilot of the responsibility for continual vigilance to see and avoid other aircraft ...

Many factors, such as limitations of the radar, volume of traffic, controller workload and communications frequency congestion, could prevent the controller from providing this service. Controllers possess complete discretion for determining whether they are able to provide or continue to provide this service in a specific case. The controller's reason against providing or continuing to provide the service in a particular case is not subject to question nor need it be communicated to the pilot. In other words, the provision of this service is entirely dependent upon whether controllers believe they are in a position to provide it.

Some questions have arisen about the Teterboro Tower's handling of the flight. Reportedly the controller was making a "non-business" phone call to the Newark tower which may have contributed to coordination problems with the handoff of the Piper from Tereboro to Newark. A conflict alert indication was shown on the radar displays at both towers as the Piper and the Eurocopter began to converge. Though these alerts usually produce both a visual and audio warning, neither controller recalled seeing or hearing the alert.

Several initial news reports made a big deal of the fact that the Piper's pilot never contacted the Newark tower after being handed off by the Teterboro tower. It's hard to know why that was, but it's also important to point out that a delay checking in after a handoff is quite common. Radio communication in aircraft is somewhat primitive - only one person can talk at a time. Perhaps the Piper's pilot was busy tuning his radio to the new frequency so he could check in, but we don't really know. It does appear that the frequency change came at a very inopportune time and the collision occurred shortly afterward. Remember all those studies that show distractions (like cell phone use while driving) reduce reaction time and situational awareness? The same thing can happen in aircraft and, apparently, in control towers.

Different Frequencies
Aircraft operating over the Hudson usually communicate using a CTAF - common traffic advisory frequency - which is like a party line where only one person can talk at a time. The CTAF is different from the frequencies used by Teterboro and Newark towers. The idea with the CTAF is that each aircraft announces their position, altitude, and intentions so that other pilots can put together a mental picture of where other traffic might be and avoid them. If this sounds primitive, it is! Yet in areas where there is no ATC service (usually at rural airports) and when there's not too much traffic, the CTAF set-up is pretty workable. The thing is that CTAF areas are usually not swarming with the volume of traffic that is seen on a daily basis over the Hudson River corridor. The important point here is that the Eurocopter was probably monitoring and transmitting on the CTAF while the Piper was monitoring and transmitting on the Teterboro Tower frequency.

Big Sky, Little Planes
This brings up the big sky theory of preventing midair collisions: The sky is big when compared to the size of aircraft, so the probability of a collision is reduced by the simple fact that the sky is so much bigger than the aircraft. This is a good theory if you assume that aircraft are randomly or evenly distributed throughout the big sky. Unfortunately, aircraft tend to congregate around certain locations (like around airports, helipads, and land-based navigation transmitters) like bees around a hive and that dramatically increases the probability of a collision.

The situation over the Hudson River adds another wrinkle since the area of airspace used by the sightseeing helicopters and other light aircraft is underneath and physically constrained by an overlying area of controlled airspace called Class Bravo. Entering Class Bravo requires a clearance from ATC precisely because this airspace was created primarily to keep small, slower aircraft away from larger, faster aircraft. When aircraft are cleared to enter Class B, ATC will guarantee separation between aircraft: This separation is not done on a workload permitting basis, it is guaranteed. This dramatically enhances the safety of aircraft operating in Class B, but ironically creates a thin layer of airspace for the smaller aircraft to share, which makes the Big Sky quite a bit smaller, and increases the probability that these smaller aircraft who are not in Class B will come close to one another.

Invisible Hands
So how about separating aircraft with a controller using radar? Air traffic control (ATC) can and does provide many valuable services to pilots by providing traffic advisories when aircraft get close or appear to be converging, but they are not an invisible hand that holds the aircraft and keeps them completely safe. Just because the pilot or flight crew of an aircraft is talking to a controller does not mean they are immune to mechanical problems, bird strikes, or midair collisions. The idea that ATC keeps aircraft safe, while not entirely a fantasy, is a belief that non-pilots may find comforting. Non-pilots need to remember that it's the pilot that is flying the aircraft and there is no invisible shield provided to aircraft that just happen to be talking to ATC.

Another misconception held by non-pilots has to do with flight plans. The idea that an aircraft is operating with an open flight plan is somehow safer than one operating without a flight plan may or may not be true. There basically are two types of flight plans: Instrument Flight Rules and Visual Flight Rules. Non-pilots need to know that the primary purpose of VFR flight plans is so that the appropriate authorities will be notified if you don't call in and close your flight plan when you arrive. In short, filing VFR flight plan helps ensure that if you crash and no one sees the crash, someone will eventually come looking for you.

Rules, Rules, Rules
Some reporters have claimed that aircraft which are not under ATC control are completely unregulated and not following any rules, but nothing could be further from the truth.

The aircraft that fly in any airspace must meet FAA airworthiness requirements including regular maintenance inspections with specific criteria.

The pilots that fly these aircraft must be certificated (we don't call them licenses in the US, but the media can't get that right either), they must hold a medical certificate, and they must meet recency experience to be able to act as pilot-in-command and to carry passengers.

The airspace in which these aircraft are operated have specific flight visibility and cloud clearance requirements. And there are specific right-of-way rules that pilots follow when they see they are getting too close to one another.

To equate these areas of airspace not under air traffic control to the Wild West is uninformed and stupid.

Technology to the Rescue, sort of

Without radar, isn't there someway that technology can keep two aircraft from trying to occupy the same airspace? It's not as if no one has tried to create technology to do this, but the success has been mixed.

Large aircraft are required to have traffic collision and avoidance systems (TCAS), but even with TCAS these planes can run into one another.

Several similar systems are available for smaller aircraft, but they can be expensive and not every aircraft has them. One system is the FAA's Traffic Information System (TIS) where appropriately configured ground radar facilities upload traffic information to appropriately equipped aircraft. This is a common system in many newer general aviation aircraft, but many ATC radar facilities do not support TIS. Oh, and the FAA is planning to phase out TIS. Yes, you read that correctly. The reason is that another system is supposed to replace TIS, even though virtually no small aircraft out there are currently equipped to support the new system. Call me a curmudgeon, but that sounds about right for the FAA ...

Another system for smaller aircraft (that is also expensive) is an Traffic Advisory System (TAS) that actively interrogates other aircrafts' transponders, just like ATC's radar. These systems can be quite helpful, but with some aircraft (like the Cirrus) there is no way to mute the aural warnings and keep them from barking "Traffic! Traffic!" when you're trying to talk to or listen to ATC.

The last system for small aircraft that I'll mention is a class of portable devices that warn of nearby aircraft and are sometimes referred to as Portable Collision Avoidance Systems (PCAS). These devices are not perfect, but they help pilots have an idea when other aircraft are nearby, even if they don't tell you exactly where those aircraft are. As a side note, I always fly with a PCAS unit.

What's a Pilot to Do?

First, scroll back to the top and watch the YouTube video of the Hudson midair. I know it's scary, heartbreaking, and painful, but watch it nevertheless.

Hopefully that video has you in a mood to listen.

Remember that accident statistics indicate that midair collisions tend to occur on clear, sunny days and usually in the vicinity of airports of navigational transmitting stations.

Keep your head on a swivel when operating in crowded airspace.

Fly at an appropriate VFR altitude for your direction of flight. I see at least one pilot violating this simple safety rule every time I fly.

Avoid distractions, like unnecessary conversations or fiddling with your GPS or MP3 player.

Listen up! Poor radio phraseology and technique not only wastes everyone's time, it can actually threaten your life, the lives of your passengers, the lives of other pilots, and the lives of people on the ground.

If you have a traffic detection device, use it.

If you think this sort of collision can't happen to you, watch the video a few more times.

You've got ...TERRAIN

The new glass panels that are quickly becoming commonplace in GA aircraft provide a wealth of information. Topography, traffic, weather. All in beautiful color. But the designers weren't content just to stimulate your retina. They also use sounds and voices to communicate with you. In fact, the only senses these systems don't seem to yet take advantage of are smell, taste, and touch.

I think most pilots can learn to selectively ignore the dazzling array of colors, when necessary. Sound is another issue. Some Cessna aircraft have autopilots and traffic information systems that beep or talk to you. The beeps and talking are quite loud. Pilots are constantly using their hearing and if these gadgets make noise at the wrong time, the results can be downright dangerous.

My first experience with these noisy bastards was the TrafficWatch system in the Cirrus. When transponder-equipped aircraft get too close, the system begins loudly barking "Traffic! Traffic!" Often, this is a great help. Other times, it's just a pain. All it takes to get the TrafficWatch blaring like you are about to die is a pilot in aircraft holding short of the runway turning on their transponder while you are on short final. Of course, you're not about to die. And there is no way to turn it off. You can momentarily stop the racket by diverting your attention to press a button. Perhaps there's a circuit breaker you can pull.

The Cessna G1000's provide a TIS traffic alerting system that, with the proper button pushes, you can turn off if you so desire. While TrafficWatch is a self-contained system that should detect any aircraft that has its transponder turned on, TIS depends on traffic information being uploaded from a properly-equipped ATC radar facility through a Mode-S transponder. Not all areas support TIS and rumor has it that the FAA has plans to phase out TIS. If this comes to pass, this will not be a boon for all the TIS-equipped aircraft out there.

One of the odd things about TIS seems to occur when you practice stalls (it's probaby the very slow airspeed) or when you transition from a non-TIS service area to an area that provides TIS. In both cases, the sytem get confused and you suddenly see a target right at you altitude, right where you are, and you hear "TRAFFIC! TRAFFIC!" Then just as suddenly, the TIS figures out that target is you and shuts up. Oh, and when you transition to an area where TIS is not supported, a voice loudly announces "Traffic unavailable". But traffic alert systems are just one of the noisy beasts in the new cockpits.

Cessna G1000-equipped aircraft with autopilots will either beep or talk to you at various times. When the autopilots disconnects or is disconnected, you will hear a loud, 2-second beep. In the Cirrus, you get a long, annoying sequence of beeps lasting several seconds that are loud enough to blot out any important sound. In a Cessna 182 I fly, disconnecting the autopilot causes a Keanu Reeves-like voice to say "Otto Piiilot!"

Dude!

When you are within 1000' of a selected altitude or you deviate from a selected altitude, you'll hear another beep or Keanu saying "Altituuude"

Dude!

If this happens when ATC is trying to tell you or ask you something, you'll probably have to ask them to "say again." Then there's the perfect noise storm - when the autopilot and the traffic alert system simultaneously vie for you attention. ATC is usually annoyed by having to repeat themselves, but they probably have no idea of the cacophony of sound occuring in some cockpits.

Today, I met a new noise-maker: A newly installed terrain awareness/warning system in a Cirrus SR22. On an instructional flight to one of my old freight dog haunts, we decided to do some touch and goes. There is rising terrain to the south of the westerly facing runway and as soon as we turned onto the base leg, a polite female voice announced "terrain." This was said in a very low-key way, like "Darling, I know you're the best pilot in the world, but you've turned toward rising terrain." Of course, we had every intention of turning away from the hillside and toward the runway at the appropriate moment, but Darling had no way of knowing this. Halfway through the base leg, about to turn final, Darling said "Terrain! Pull up!" with a "Honey, you're starting to scare me" sort of intonation. I thought when we turned final that Darling would relax, but she was wound up really tightly. "Terrain! Pull UP! Pull UP!" she insisted as we approached the runway. The pilot I was instructing was flying and he remained remarkably calm.

I was now resolved to find a way to turn Darling off, but try as I might, I couldn't find a way to disable the voice. I did find a menu item called "Disable Terrain" on the #2 Garmin 430, but selecting it had no effect. I plan to research this further. If anyone knows how to turn off the terrain voice, I'm all ears, as it were. And if you think I'm sexist, let me add that there is a male voice in a Bendix/King-equipped aircraft I fly that barks "Traffic! Traffic!" with such intense intonation that the first time I heard it, I nearly jumped out of my skin.

There is technology available to sort out this mess. My LightSpeed Mach1 headset has an auxiliary audio input for music, like an MP3 player. If listening to an MP3 player while flying sounds dumb, then the Mach1 is smart. When it senses someone talking over the intercom or ATC trying to say something to you, it automatically reduces the volume of the auxiliary audio by about 70%. It is remarkably effective and it happens so quickly, it seems like the unit has ESP. Why can't Garmin, King, BF Goodrich, and the others find a way to do the same with all the voices, beeps, and alarms? Seems to me that only the audio panel/intercom would need to be modified.

I used to fly to get a peaceful feeling. Now, sometimes the only time I feel peaceful is on the drive home.