Dette gjelder både for fly- og helikoptre. Det pussige er at ingen synes interessert i å diskuterer to sertifiserte flygere når en flyr med betalende passasjerer, også innen luftambulansen. Heller ikke i artikkelen under diskuteres det. IHST, International Helicopter Safety Team eller USHST, har heller ikke diskutert dette. I alle fall så vidt jeg vet. En kan ikke erstatte flyger nr. 2 med klokker, varsler og blinkende lys. Det er mellom ørene det sitter. Nå drar jeg på ferie en ukes tid. Kos deg med denne flotte artikkelen. (Red.)
One of the most disorienting and dangerous things that can happen to a pilot during flight is inadvertently entering Instrument Meteorological Conditions (IMC). While this is a known hazard and can be easily avoided by thorough preflight preparation and in-flight weather observation, it still occurs fairly regularly. Three weeks ago, it likely happened to the helicopter carrying retired NBA star Kobe Bryant and eight other people. That flight ended in tragedy with the death of all aboard. Twenty years ago, the same thing almost happened to me in the same area.
My crew and I escaped that near catastrophe with our lives by the narrowest of margins. The reality is that it can happen to anyone, from the private pilot on a weekend recreational flight to the passenger-carrying helicopter pilot on a routine hop with a beloved sports star and his friends and family onboard to the most capable and well-trained military pilot. Here’s what we know about the Kobe flight and why it reminded me of my own brush with death.
Doomed Flight
There is a tremendous amount of confusing and even misleading information in the public domain about this tragedy and how helicopters are operated, in general. So, before I get to my own story of experiencing a very similar situation while flying HH-60H Seahawk helicopters in the Navy, let's break it all down in order to provide a comprehensive picture of the circumstances surrounding the incident.
What started out as a routine helicopter flight two weeks ago from John Wayne Airport in Orange County, California, to Camarillo Airport in Camarillo, California, ended in tragedy when the Sikorsky S-76 helicopter crashed into a hillside in Calabasas, California. Bryant, his 13-year-old daughter Gianna, and seven other people died in the crash.
While the final report from the National Transportation Safety Board (NTSB) will not be completed for some time, there is enough evidence in the public domain and within the NTSB Aircraft Accident Investigative Update released on February 7th to make some informed observations about the incident.
NTSB
The helicopter involved in the crash.
In this case, the helicopter was single piloted on a Visual Flight Rules (VFR) flight plan. During the flight, the pilot observed weather conditions degrading and asked for and received permission to continue the flight under Special Visual Flight Rules (SVFR), which we will discuss in detail in a moment.
While the helicopter type, the Sikorsky S-76, is certified for flight in Instrument Meteorological Conditions, the operator of this specific airframe, Island Express Helicopters, had an operating certificate from the Federal Aviation Administration (FAA) that limited its operations to Visual Meteorological Conditions (VMC) only.
In other words, while this individual S-76 helicopter may or may not have been capable of IMC flight, it was not authorized for it. Shortly before crashing, the helicopter appears to have inadvertently entered IMC and began maneuvering aggressively, possibly in an attempt to escape those conditions.
Meteorological Conditions, Pilot Ratings, Aircraft Certifications, And Flight Plans
In order to understand the sequence of events that led to the tragic death of nine people, we need to understand some basic terminology and regulations that describe meteorological conditions, pilot ratings, aircraft certifications, and flight plans.
In terms of weather, there are two basic classifications of meteorological conditions that apply to flight operations. These are Visual Meteorological Conditions (VMC) and Instrument Meteorological Conditions (IMC). The parameters that determine these classifications are set by the FAA with respect to visibility, cloud ceiling, and separation from clouds, both vertically and horizontally, during flight.
These VMC minimums vary according to the type of airspace that is being flown in. VMC and IMC are mutually exclusive conditions. At any given time, every major airport in the United States with a control tower operates under either VMC or IMC conditions based on actual local weather observations.
In terms of operating aircraft, pilots are licensed, certified, and rated by the FAA in a number of different categories, like a private or commercial pilot or certified flight instructor. All pilots qualify under VFR conditions and may obtain an advanced instrument rating that authorizes them to fly in IMC.
With respect to what type of weather that specific aircraft can fly in, each individual aircraft operating in the United States must obtain an airworthiness certificate before operating. Every aircraft, at a minimum, is authorized to fly in VFR conditions. In order to legally operate under IMC conditions, aircraft must have additional equipment, including heading indicator, attitude indicator, altimeter adjustable for barometric pressure, two-way radio, transponder, and specific navigation equipment. In general, the required navigation equipment varies based on the date of manufacture of the airframe.
NTSB
In terms of flight plans, any flight that goes into the FAA's airway system must file an Instrument Flight Rules (IFR) flight plan prior to takeoff, regardless of the weather conditions. Flights that do not use the FAA airway system should file a VFR flight plan. Special Visual Flight Rules (SVFR) is a unique category of flight clearance. It is used when an aircraft operating under VFR rules encounters weather that meets the criteria for IMC conditions, but where continued safe operation is possible under VFR rules.
With the basic definitions and terminology of weather, pilot ratings, aircraft certifications, and flight plans in place, let's consider what happened in this specific instance.
Sequence Of Events Leading To The Crash
We have a pretty good amount of detail on the sequence of events leading to the crash, especially with the help of the FAA's preliminary report on the incident.
Regarding the helicopter and pilot, we know that the mishap helicopter was single piloted and on a VFR flight plan. Ara Zobayan, the pilot of the helicopter, had commercial pilot, rotorcraft (helicopter), and instrument helicopter ratings. This means he was qualified to fly a commercial helicopter, with paying passengers, under IMC conditions on an IFR flight plan, as long as that individual helicopter and operator company was certified for flight in IMC. In this case, even though he personally was qualified to file and fly IFR flight plans, the company he worked for, Island Express Helicopters, was only authorized to file and fly VFR flight plans.
This is not unusual. It is very common for helicopters to only operate in VMC conditions, on a VFR flight plan. A VFR flight plan simply requires that the aircraft remain clear of controlled airspace, unless in two-way radio communication with air traffic control (ATC) for a temporary transit through controlled airspace, and to remain clear of fog, clouds, rain, or any other weather condition that would obscure visual reference to navigational checkpoints on the ground. The vast majority of helicopter flights in the United States take place under VMC conditions, under VFR rules.
The most direct route of flight from John Wayne Airport to Camarillo Airport is to head northwest over Los Angeles, then continue over the Santa Monica Mountains. This course would take the aircraft directly through Los Angeles International Airport's (LAX) Class B airspace. Accordingly, the flight path would have to deviate to the east around that Class B airspace or follow an established VFR transition route through that airspace. This route of flight going near LAX and then over the Santa Monica Mountains to Camarillo had been used by Island Express Helicopters on a number of previous flights and the pilot Ara Zobayan had flown this VFR route the previous day.
Regarding the weather at the time of launch, both fog and a low cloud layer were present which precluded the direct route of flight over the Santa Monica Mountains. The Los Angeles Police Department grounded its helicopter flight operations that morning due to fog and low clouds.
One of the consistent local weather phenomena in Southern California is the presence of a marine layer of fog that can develop over the ocean and quickly moves inland. With poor weather reported and observed near the coast, the pilot reasonably decided to divert his route further inland, to the east. Rather than flying northwest over Los Angeles into fog and clouds, he flew to the east of downtown Los Angeles towards Glendale.
NTSB
After flying east of downtown Los Angeles, according to data posted on Flightradar24, the helicopter completed six holding turns over Glendale. Holding turns are used when a flight needs to delay its progress before continuing on course, and may vary in duration, altitude, and geometry depending on the location and reason for holding. The most common cause of holding turns is in response to direction from air traffic control to facilitate proper spacing and sequencing of flights.
In addition to responding to direction from air traffic control to enter holding, aircraft may also initiate a request to enter holding. One of the most common causes of holding requests from aircraft to air traffic control is to avoid dangerous weather conditions.
Based on transcripts posted on LiveATC.net and the NTSB update, the helicopter entered holding over Glendale in response to direction from air traffic control to facilitate traffic flow into and out of Hollywood Burbank Airport, located just northwest of Glendale. There is no indication in these transcripts that the weather had anything to do with the initial direction from air traffic control to hold and no indication that the pilot requested to hold.
Flightradar24.com
The final flight path of the helicopter including the holding turns over Glendale.
After completing holding turns in order to facilitate traffic flow, the pilot then requested permission from air traffic control to proceed through Burbank Airport airspace under the aforementioned SVFR rules. Because Burbank Airport is designated as Class C airspace, the weather minimums to operate under normal VFR flight rules are three statute miles visibility with aircraft operating at least 500 feet below, 1,000 feet above, and with 2,000 feet of horizontal separation from clouds.
Based on air traffic control communication and the pilot's request to fly through Burbank airspace under SVFR rules, we can conclude that the weather was below VFR minimums at that point. There is nothing inherently unsafe about flying in SVFR conditions, as long as the pilot is trained to fly in such conditions. Of course, flying in SVFR conditions does present a greater risk than flying in VFR conditions, which is why FAA regulations prohibit air traffic control from suggesting this option to pilots. If a pilot wants to fly in marginal weather below VFR, the pilot must initiate the request to air traffic control to fly in special VFR conditions.
NTSB
According to an audio clip of the radio communications between Zobayan and air traffic control posted online and from the NTSB's recent update, as the pilot transited through Burbank Airport airspace he relayed his route of flight intentions to air traffic control. Based on that conversation, his intended route of flight was to follow Interstate 5 to the northwest of Burbank Airport, then California State Route 118 to the west, closer to his intended destination at Camarillo Airport. This route of flight allowed for an expeditious transit through Burbank Airport airspace and also kept the helicopter clear of Van Nuys Airport, which is located just west of Burbank Airport. Following major freeways and roads is a very common navigation technique used by helicopter pilots operating under VFR flight plans.
After following Interstate 5 and State Route 118 around Burbank and Van Nuys airspace, the flight continued in a westerly direction towards Thousand Oaks. At that point, it was positioned for a relatively direct path further to the west to Camarillo. Unfortunately, that path had rising terrain both to the north and south and was experiencing degraded weather conditions.
Shortly after that final radio communication, the helicopter turned sharply left, heading south, and then entered a steep rate of descent as it continued the left turn to nearly due east, and crashed into a hillside. At the time of impact, Automatic Dependent Surveillance-Broadcast (ADS-B) transponder and radar data referenced by the NTSB update showed that the helicopter was in a left turn, descending at over 4,000 feet per minute and 161 knots immediately before impact.
NTSB
Regarding the weather at the time of the crash, the Weather Channel reported that clouds and fog were present. Shortly after the crash, the Los Angeles County Sheriff's Department posted a picture showing a layer of fog or low clouds directly above the crash site. One eyewitness reported hearing the helicopter shortly before the crash, but could not see it due to the low cloud layer. Another eyewitness was hiking near the scene of the crash and reported seeing the helicopter emerge from the clouds in a descending and turning flight path immediately before crashing.
Analyzing The Data For Causation
In the early history of aviation, the vast majority of mishaps were caused by a mechanical malfunction. As aircraft design, manufacturing, and maintenance processes have improved in modern times, mechanical malfunctions have decreased as a causal factor for mishaps. According to the FAA, the vast majority of modern air mishaps are caused by human error. While we cannot conclusively state at this point that this crash was caused exclusively by pilot error, it is very plausible, if not probable, based on the information we have, that the pilot made a mistake by inadvertently flying into IMC conditions.
Regarding the data showing the helicopter moving at 161 knots and descending at over 4,000 feet per minute at the moment of impact, these are well outside the normal operating parameters of the S-76 helicopter. There is simply no reason for a helicopter in IMC conditions, with passengers on board, to intentionally enter a rate of descent over 4,000 feet per minute and exceed the maximum cruising speed of the aircraft (155kts), especially when operating at low altitudes.
As a comparison, the H-60 Seahawk helicopter, a high-performance military helicopter that I piloted for 20 years in the Navy, had a normal descent rate of about 500 feet per minute while on instrument approaches. In some circumstances, depending on airspeed, terrain, and other traffic in the area, the helicopter might have a decent rate of up to 1,000 feet per minute during certain maneuvers. Anything above that is outside the normal operating envelope, even if the aircraft is mechanically capable of higher rates of descent.
The only time I experienced a 4,000 foot per minute rate of descent was during fully developed, power off autorotations or maximum performance powered descents, which only happen under very specific conditions requiring both high speed and high rate of descent.
While it is extremely unlikely that this helicopter encountered a mechanical malfunction that required a fully developed, power off autorotation or a maximum performance powered descent, there are some technically plausible scenarios that could have caused this.
The NTSB has ruled out catastrophic engine failure as a causal factor. In this context, this means NTSB has concluded the engines did not disintegrate in flight. With that said, it is possible that the helicopter suffered a dual engine failure without it being a catastrophic failure.
Such scenarios are extremely uncommon, but they do happen. U.S. Airways Flight 1549, a fixed-wing Airbus A320 airliner, experienced a bird strike in flight which caused both engines to shut off, resulting in a forced landing into the water in 2009. You can see the NTSB animation and air traffic control recordings related to that mishap here.
NTSB
If this S-76 helicopter encountered a dual bird strike into the engine intakes, it is possible it suffered a dual engine flameout, the only response to which would be an autorotation. Such an engine failure would not necessarily result in immediately identifiable damage.
Another possibility is contaminated fuel leading to a dual engine flameout, necessitating a fully developed autorotation. As far as powered maximum rate of descent goes, if a fire occurred in the cockpit or cabin, that would necessitate an immediate powered maximum rate of descent to find the first survivable landing zone. Because the post-crash fire consumed much of the helicopter wreckage, and because the helicopter was not equipped with a Cockpit Voice Recorder (CVR) or Flight Data Recorder (FDR) "black boxes," which might have contained evidence of an onboard fire, it will be more challenging for the NTSB to conclusively rule this possibility out.
An onboard fire was the exact scenario that led to Swissair Flight 111, a fixed-wing McDonnell Douglas MD-11 airliner, crashing just off the coast of Nova Scotia, killing all 229 passengers and crew on board, in 1998. You can read the Transportation Safety Board of Canada report on that accident here.
Flying in IMC presents no mechanical challenge to the helicopter. It doesn't matter to the aircraft if it is flying in clear air or clouds. It is simply an issue of whether or not the aircraft is equipped with the proper instruments for flight in IMC conditions and whether or not the pilot is capable of flying on instruments with no external visual reference. Currency in training for these conditions is a factor as well.
As far as loss of control of the aircraft by the pilot, that is a plausible causal factor. Operating in poor weather at relatively low altitude and with rising terrain on either side of the aircraft, it simply isn't reasonable that the pilot intentionally entered an extremely high rate of descent at high speed during a course reversal (a rapid about-face in direction of flight).
Based on all of these data points and my extensive experience flying helicopters in marginal weather conditions, all factors seem to indicate the pilot inadvertently entered IMC, then executed a sharp turn in an attempt to return to VMC conditions, shortly before crashing. This is not to say conclusively that the flight crashed because of the pilot error of inadvertently entering IMC. It is possible that the pilot entered inadvertent IMC, then suffered a mechanical malfunction that caused the crash. We won't know the full cause of the crash until the NTSB finishes its final report, which may take up to 18 months.
Accident Investigation And National Transportation Safety Board (NTSB)
Shortly after the crash, the NTSB activated its "Go Team" and sent 18 accident investigators to the crash site. According to the NTSB, the purpose of the Go Team is to respond to the site of a major accident as quickly as possible. This team, working in coordination with local law enforcement, secures the crash site and starts the laborious process of collecting all the physical evidence at the scene. This is especially important if a mechanical malfunction was the cause of the crash.
Modern investigative techniques and technologies are able to determine with a high degree of accuracy whether or not the main components of the airframe were functioning correctly at the time of the crash, but only if the crash site is secured from contamination and disruption. Following the recovery of the components, typically the airframe is rebuilt in a hangar so investigators can see the entire structure, or at least what is left of it.
Without any help from the cockpit voice recorder or flight data recorder (FDR) "black boxes," the NTSB investigation will have to rely on data collected external to the aircraft, including air traffic control voice and radar recordings. While the crash occurred on an uninhabited hillside, numerous eyewitnesses observed the helicopter immediately prior to it entering IMC conditions, or heard it while it was in IMC conditions, and their statements will also be part of the investigation.
YSSYguy/wikicommons
Flight Data Recorders and Cockpit Voice Recorders that are hardened to survive crashes have become increasingly miniaturized and tailored to the airframes that host them. New models combine both functions in one Box.
Even without the black boxes, the wreckage of the helicopter may confirm or rule out the rather remote possibility of the aircraft suffering a mechanical failure prior to the crash.
NTSB vs. FAA
One issue that becomes readily apparent in the aftermath of this crash is the tension between the NTSB and the FAA. The former agency investigates and makes recommendations; the latter is responsible for actually implementing regulations.
Based on earlier crashes involving S-76s, the NTSB had made several recommendations to enhance safety of flight, as well as assist in data collection as part of mishap investigations.
Specifically, in an Aircraft Accident Report (AAR) resulting from an S-76 crash in 2004, the NTSB previously recommended that the FAA mandate installation of the Terrain Awareness and Warning System (TAWS) on all "existing and new U.S.-registered turbine-powered rotorcraft certificated for six or more passenger seats."
The FAA did not concur with this recommendation and it was never implemented. Additionally, the NTSB recommended as part of that same report that the FAA "require all rotorcraft operating under 14 Code of Federal Regulations Parts 91 and 135 with a transport-category certification to be equipped with a cockpit voice recorder (CVR) and a flight data recorder (FDR)." As with the recommendation for TAWS, the FAA did not concur with the recommendation to mandate installation of CVR or FDR.
The S-76 that crashed with Kobe Bryant and other passengers on board was not equipped with TAWS, CVR, or FDR. Had the S-76 been equipped with TAWS, it may have helped the pilot maintain situational awareness with respect to the rising terrain on both sides of his aircraft. Had the S-76 been equipped with a CVR and FDR, the NTSB investigation would certainly be informed with more accurate data to determine the exact cause of this crash.
An example of a TAWS system for helicopters:
While the external data collected from air traffic control radar and radio logs helps, it does not record the multiple, minute details only available from data collection internal to the aircraft, such as pitch and roll attitude, power setting, control inputs, and much more. A CVR would add another layer of critical and far more nuanced evidence. All this would be accessible very quickly if the recorders were successfully retrieved from the wreck.
While I take no position on whether the NTSB or FAA is correct on the issue of mandatory installation of TAWS, CVR, and FDR, I am confident that this high profile fatal accident will reignite the debate on what equipment should be mandatory onboard helicopters carrying paying passengers.
Photo by David McNew/Getty Images
NTSB works to examine and remove wreckage from the Santa Monica Mountains.
For now, we will just have to wait for the official NTSB report to find out exactly what caused the crash. Suffice to say it seems very likely that NTSB will apportion some fault to the pilot for entering IMC conditions. While that is a grievous error that likely played some role in the crash, it is also an error that many other experienced pilots have made.
I know I did and it almost killed me, my copilot, and my two aircrewmen.
Going Inadvertent IMC Is Easier Than You Think
During a 20 year career as a Naval Aviator, I accumulated over 3,000 hours in H-60 Seahawk helicopters. On more occasions than I would like to remember, I inadvertently flew into IMC conditions. It happens more often than you might think, particularly in the Navy.
For a variety of cultural reasons, Naval Aviators adhere to the motto of "if it is not expressly prohibited, it is allowed." This can be a great standard for achieving operational excellence and mission accomplishment, but it is an inherently risky approach to flight planning and execution.
In any case, the closest I came to crashing was due to inadvertent IMC, and oddly enough, it happened about 20 miles west of where Kobe Bryant's helicopter crash occurred.
It Was A Routine Flight To Practice Instrument Approaches
While stationed at Naval Air Station North Island (NASNI) in San Diego as an Instructor Pilot (IP), I would occasionally fly students up the coast to Naval Air Station Point Mugu, which is right on the coast and about five miles due south of Camarillo Airport. The vast majority of our instructional flights took place between NASNI and Naval Outlying Field Imperial Beach, about 10 miles to the south, but for some syllabus flights, we would get the students out of the local area.
On this particular flight, we were going to practice multiple precision and non-precision instrument approaches, so I decided to go up the coast to Point Mugu, which is far less congested airspace than San Diego. By definition, in order to fly instrument approaches, you have to be on an IFR flight plan, so we filed the flight plan, took off, and headed up to Point Mugu.
Because airspace in Southern California is so congested, and because helicopters fly much slower than the fixed-wing commercial traffic that dominates the air traffic controllers' workload, we typically would either request or accept non-standard flight routing to make it easier on air traffic control and ourselves. Our maximum speed in the helicopter was close to the minimum speed for most commercial airframes, so to avoid conflict with that traffic, we would occasionally file and fly point to point routing that was not part of the standard airway system.
In this case, we filed to fly direct from NASNI to Naval Auxiliary Landing Field on San Clemente Island, direct from there to Naval Outlying Field San Nicolas Island and from there to Naval Air Station Point Mugu. It was a legal IFR flight plan, all over water with no conflicting traffic. Southern California air traffic control was happy to give us offshore routing to keep out of that beehive airspace.
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A Seahawk off Naval Air Station North Island in San Diego.
We flew up to Point Mugu and I planned on staying there for about an hour, doing about five precision and five non-precision instrument approaches. I figured with the good weather we could request short legs on our instrument traffic pattern. For the first seven or eight approaches, everything went like clockwork. It was a late Friday afternoon, there was no airborne traffic at Point Mugu, we were the only aircraft in the pattern, so we were getting short leg approaches and easy passes.
When Complacency Sets In, Danger Is Close Behind
I thought we were in for a quick wrap up to the flight, an easy transit back down the coast to San Diego, and a fun start to the weekend. As my thoughts wandered, I failed to notice that the marine layer of fog was building up from underneath the helicopter at the same time a cloud layer was descending from above. Point Mugu tower and approach control should have told us that the weather was degrading, but it's possible they were not paying attention. We sure weren't.
There were no other aircraft in the pattern and our outbound legs were heading at 210 degrees, which took us almost directly into the setting sun before turning back on final to take the approach to runway 030. On our last approach, as we were flying the downwind leg directly into the sun, we couldn't see squat. I assumed, incorrectly, that it was just the haze of flying into the sunset. In fact, we were entering IMC conditions and were completely unprepared for it. As we turned towards the final heading, now flying away from the sun and into darkness, I started to pick up that conditions were changing rapidly.
Google Earth
NAS Point Mugu facing south with the nearby Santa Monica mountains clearly visible.
For all the previous approaches, we could see the runway through the entirety of the approach. This time, we couldn't see anything except the fog beneath us. In the five minutes since our last approach, fog had completely obscured our sightline to the airfield. At the same time, I saw a solid wall of clouds ahead of us.
Since we were on an instrument approach and on an IFR flight plan, there was no problem flying into the cloud, but I had not done the IMC checklist. We had flown up to Point Mugu on an IFR flight plan, but since the weather was so clear, we had not actually configured the aircraft for flight in IMC conditions.
From Unaware Of IMC To Unprepared For IMC
When transiting from VMC to IMC conditions, there are a number of aircraft settings that need to be reconfigured.
For example, the anti-collision lights need to be off. Having anti-collision lights illuminating inside a cloud and reflecting back into the cockpit can be disorienting and even vertigo-inducing. The pitot heat should be on anytime the aircraft is flying through visible moisture, whether rain, clouds, or fog. The pitot-static system provides inputs for many of the instruments required to fly safely in IMC conditions and if it accumulates water, it can malfunction. It seems like a small thing, but ice crystals in the pitot tubes leading to inaccurate airspeed indications was one of the causal factors of the Air France Flight 447 mishap, which involved a fixed-wing Airbus A330 airliner, in 2009.
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Seahawk cockpit and crew.
Once I saw we were about to go IMC, I took the controls from my student and directed him to configure the cockpit for IMC operations. As we entered the cloud, I realized our instrument panel lights were completely off. This is normal during daytime VFR conditions. You don't need your instruments backlit if you can see them with ambient light, but given that I had just flown into a cloud, I needed my instrument backlighting turned on as soon as possible. My student copilot fumbled in the dark, couldn't quite find the correct switch and instead inexplicably turned on his flashlight and shined it in my face, temporarily blinding me. I resisted the urge to beat him senseless and continued to fly the aircraft.
That was the point where I first realized we were in serious trouble, flying in total IMC, with no instrument panel lights on, and this regrettable, avoidable, and potentially fatal situation was entirely my fault.
Fortunately, we got the instrument panel lights on and equipment correctly configured and at that point I called air traffic control to cancel the approach and get vectors to establish back on my IFR flight plan to return to San Diego. I figured we could do our last required instrument approach or two back at NASNI.
Controllers Are Human And Make Mistakes Too
We canceled the approach and air traffic control acknowledged, but like us, the controller had not been paying attention and was unprepared to give us vectors to get out of the approach pattern and back onto our IFR flight plan. The controller instructed us to maintain runway heading and 500 feet altitude while he coordinated our return to San Diego.
A word about altitude management: air traffic control clearances are always given in altitude with reference to Mean Sea Level (MSL). 500 feet MSL does not necessarily mean 500 feet Above Ground Level (AGL). I knew this, but was about to get a very rude reminder of it.
Another note about air traffic control. It was obvious with us being the only aircraft in the pattern on a lazy Friday evening that the controllers simply were not paying attention to us until the point where we canceled the approach and requested vectors offshore to get back on our flight to San Diego.
At this point, we had flown several miles past the runway threshold, but we were still holding at 500 feet MSL, our last assigned altitude. I called air traffic control and asked for the status of our request for vectors back to San Diego. The controller told me to turn right to 180 degrees on the compass, otherwise known as south.
All our previous turns for the practice approaches had been to the left, away from the Santa Monica Mountains, to a downwind heading of 210 degrees, exactly opposite of our final approach course of 030 degrees to runway 030. For some reason, this controller at this point lost situational awareness and turned us toward the mountains, which I could not see, because we were completely in the clouds. I knew the mountains were there, but, and there is no way to say this without sounding like an idiot, in the transition from VMC to IMC I simply forgot about them.
As I rolled out heading 180 degrees I reacquired situational awareness of the existence of the mountains, but did not know where they were relative to my aircraft and thought we must be clear of them, because there is no way air traffic control would give me vectors at low altitude into rising terrain.
The Grim Reaper Enters The Equation
At this point, I knew something was wrong, but wanted to figure out what it was before I called air traffic control. As that thought went through my head, I saw my radar altimeter rapidly spinning down. Overwater, the radar altimeter and barometric altimeter should read more or less the same. In this case, my barometric altimeter showed stable at 500 feet MSL, but because I was flying into rising terrain, my radar altimeter showed a constantly decreasing altitude above ground level.
In an instant, I realized what had happened. I knew I was flying straight towards a mountain and my radar altimeter was displaying the constantly decreasing separation between me and the rising terrain I was flying over. We were within five seconds at most of crashing, probably closer to three seconds, and the overwhelming emotion I experienced was not fear, but rage.
How could I have been so stupid?
Two options flashed through my mind. I could maintain heading and simply apply maximum power and try to execute a low speed, maximum performance climb to get over the mountains. This would have been the easiest option in terms of control inputs and aerodynamics. It would only have required a slight nose back adjustment to trade forward airspeed for vertical altitude, and application of maximum power. The other option was to roll into a maximum angle of bank turn, also at maximum power to turn away from the rising terrain.
I took the turn option and rolled into a 45-degree angle of bank turn to the right, and applied maximum power. Rather than use the extra power to try to climb, I thought I had a better chance of avoiding the crash if I used the power to increase my rate of turn and tighten my radius of turn.
As I did this, I heard a different controller from air traffic control radio me in a panicked voice to turn right immediately to avoid rising terrain. I did not acknowledge the transmission as I was already executing the turn and wanted my total concentration on completing a high angle of bank turn at maximum power in total IMC conditions. That's a situation tailor-made to depart controlled flight and I knew my priorities were to aviate, navigate, then communicate. So I simply didn't respond to air traffic control.
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Example of an air traffic control tower at a Naval Air Station, in this case, NAS North Island.
At the same time, as I rolled into the turn, I watched the radar altimeter continue to wind down and started its aural warning beep as we got within 100 feet of the ground beneath us. WIth 99 percent power set at a 45-degree angle of bank, the aircraft was at or near its maximum turn rate, but still, the radar altimeter continued to display the decreasing distance between the aircraft and the ground.
It didn't last more than three or four seconds, but it felt like forever as I saw the readout go from 100 feet above ground level to 80 feet and then 60 feet before showing a rapid increase in altitude, indicating we were now flying away from the rising terrain. I continued the turn past 270 degrees to 360 degrees for just a little extra peace of mind. I cross-checked my magnetic and electronic compasses to make sure I really was heading directly away from the mountains. They matched, and I breathed a sigh of relief.
Alive And Headed Home
Of course, I had traded one problem for another. Air traffic control had given me bad vectors, I initially accepted them, then of my own accord changed my route of flight to avoid the mountains. Now I was flying on a path directly between NAS Point Mugu and Camarillo Airport without vectors or altitude direction from air traffic control all while in total IMC.
I keyed my microphone to call in just as yet another air traffic control chimed in and asked "Where are you going? What is your request?" I replied in a voice shaking with post adrenaline dump nervousness, "I just need vectors offshore to pick up my IFR flight plan back to San Diego."
Two minutes later we were overwater, heading directly for San Nicolas Island, then San Clemente Island, then San Diego. Enroute, I debriefed the crew on what had happened. I don't think any of them realized how close we had come to crashing. I told them air traffic control had given us bad vectors and that I accepted those vectors because I had lost situational awareness of where the mountains were.
Ted Eckmann/UCSB.edu
The fog manifests seemingly out of nowhere and suddenly around the Santa Monica Mountains and especially near NAS Point Mugu.
By the book, I should have filled out a safety report when I got back to San Diego. While I blamed myself, air traffic control also made some mistakes and I should have documented both sides of the problem. I didn't make a conscious decision to not submit a safety report, I just didn't do it. I think I was so stunned by the whole episode. By the time we got back to San Diego, to a nearly deserted hangar on a Friday night of a three day weekend, it just didn't occur to me to do the right thing and document it.
I was just happy to be alive.
IMC May Be Unavoidable, But Should Never Be Inadvertent
There is rarely an excuse for experiencing inadvertent IMC. Flying into IMC conditions may be unavoidable, but it should never be inadvertent.
With that said, almost every pilot I know has made this same mistake at one time or another. I can’t say conclusively that the crash that killed Kobe Bryant, his daughter, and their friends was because the pilot, Ara Zobayan, inadvertently entered IMC conditions. I can say that when I did something similar, I had a vastly better set of circumstances to rescue me from the consequences of my poor decisions than he did.
I had an overpowered and lightly loaded military aircraft that was equipped and certified to fly under complete IMC conditions. I trained regularly to fly in complete IMC conditions. I had a competent copilot to configure the cockpit instruments and give me verbal backup on my instrument scan, and I was under constant (if temporarily incorrect) air traffic control guidance to vector me to safety. Even with all those advantages, I came within a second or two of crashing into the side of a mountain not far from where Kobe's S-76 did the same.
While it may sound crazy to the average person that any licensed professional pilot could fly directly into conditions that they were not prepared for, the cold hard truth is that it is not uncommon. Every helicopter pilot who has flown long enough has experienced a similar situation or some other avoidable brush with death. It is the unadvertised nature of the job.
Editor's Note: We reached out to Island Express Helicopters for comment and they declined to comment at this time.
Chris Harmer is a retired Naval Aviator. He flew SH-60F and HH-60H helicopters, accumulating approximately 3,500 total flight hours. During his career, he was designated as both an Instructor Pilot and a Seahawk Weapons Instructor Pilot, and is a graduate of the Navy's Mountain Flying School. He has flown training and operational missions in the airspace of over 50 different countries. He is a regularly scheduled military and national security analyst on multiple cable television networks including Fox, CNN, MSNBC, and BBC.
Contact the editor: Tyler@thedrive.com
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