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Rumblings from Independence Avenue: Trouble Ahead for HEMS?

Posted 13 years 94 days ago ago by Admin

By Bill Winn - The sound of thunder on the near horizon can herald hope or fear, depending on whether you are a drought-stricken farmer or a Golden Retriever with a serious phobia of both the boom and flash of lightening. My dog Max literally climbs into bed between me and Joyce during every thunderstorm, and lies there shivering uncontrollably until the storm has passed. It's like having one of those vibrating beds you find in cheap motels.


As a member of the air medical transport community, I know I speak for many when I say that the rumblings currently emanating from the FAA headquarters building at 800 Independence Avenue are a source of both hope and dread. I refer to the NPRM (Notice of Proposed Rule Making) currently under consideration that purports to implement some of the most far reaching changes to FAR Part 135 in recent history. The proposed new rules are motivated by the disturbing trend in air medical helicopter accidents in recent years, and there is hope that the changes will be effective in improving the safety of patient transport operations. But, there is also acute concern that if the total impact of the rules is not very carefully considered before implementation, then some elements of the new rules may hinder air medical providers from delivering their life saving services without effectively targeting the most significant root causes of many air medical accidents. There is also a widespread sentiment among EMS pilots that the NPRM has missed the mark with respect to selecting the most effective technology to use to mitigate the problem of accidents resulting from controlled flight into the terrain (CFIT).

A summary of the proposed new rules and revisions to existing regulations is contained in the following table, taken from the NPRM.

Affected Entities


Part 135 – All Aircraft

·       Permit operators to transmit a copy of load manifest documentation to their base of operations, in lieu of preparing a duplicate copy.

·       Specify requirements for retaining a copy of the load manifest in the event that the documentation is destroyed in an aircraft accident.

Part 91 – Helicopter

·       Revision of part 91 Visual Flight Rules (VFR) weather minimums.


All Commercial Helicopter Operations (Operating Requirements)

·       Revision of commercial helicopter instrument flight rules (IFR) alternate airport weather minimums.

·       Require helicopter pilots to demonstrate competency in recovery from inadvertent instrument meteorological conditions.

·       Require all commercial helicopters to be equipped with radio altimeters.

·       Change definition of “extended over-water operation,” and require additional equipment for these operations.


Air Ambulance Operations (Operating Requirements and Equipage)

1.     Require air ambulance flights with medical personnel on board to be conducted under part 135, including flight crew time limitation and rest requirements.

2.     Require certificate holders with 10 or more helicopter air ambulances to establish operations control centers.

3.     Require helicopter air ambulance certificate holders to implement pre-flight risk-analysis programs.

4.     Require safety briefings for medical personnel on helicopter air ambulances.

5.     Amend helicopter air ambulance operational requirements to include VFR weather minimums, IFR operations at airports/heliports without weather reporting, procedures for VFR approaches, and VFR flight planning.

6.     Require pilots in command to hold an instrument rating.

7.     Require equipage with Helicopter Terrain Awareness and Warning Systems (HTAWS), and possibly light-weight aircraft recording systems (LARS).


All NPRM's proposed by the FAA have a public comment period which allows individuals and organizations the opportunity to submit written statements to the FAA to either critique or express support for the individual elements of the proposed rules. The comment period for the rules summarized in the preceding table ended on January 10. At the close of the period there were 331 public submissions on file at the official website for NPRM comments at www.regulations.gov. Those comments were submitted by a wide variety of players in air medical transport, including air medical operators, professional associations, specific air medical provider services, aircraft and aircraft systems manufacturers, State and local government agencies, and more than just a few individuals (mine is there). All of these commentators were eager to express their support of those elements of the NPRM that seemed most likely to have a positive effect on safety, while pointing out the flaws or omissions in the proposed rules that might hinder the delivery of air medical services without materially improving operational safety.

The full text of all of the comments submitted is available on the government website for those readers who have sufficient interest, time, and caffeine to read them. In this article, I will touch on only a few of the new rules which I feel threaten to be the most problematic for all air medical transport providers. Those rules are the ones numbered 1 and 7 in the Air Ambulance section of the table, above.

Impact on air medical transport services

In an FAA legal letter dated 7 June 1990 it stated that,

"When an aircraft is owned by a hospital and all the people, which are carried aboard that aircraft during a particular flight (i.e., pilot and medical personnel), are employees of that hospital (a patient is not in the aircraft), a flight could be conducted under Part 91 of the FAR".

But, the new proposal  will require helicopter EMS (HEMS) providers to conduct all flights under FAR Part 135 whenever medical personnel are on board, whether or not there is a patient on board and whether or not those medical personnel are employees of the Part 135 certificate holder. This is especially problematic for (at least) two reasons.

The first reason is simply that the rule is inconsistent with the parallel rule in FAR part 121 which allows airline pilots to operate under FAR Part 91 for a flight where only employees of the operator are on board. Even though many Part 121 operators may opt to demonstrate their commitment to safety by specifying in their Operations Specifications (OpSpecs) that they will operate under Part 121 rules at all times, the point is that they have a choice. That choice will not be extended to air medical provider services under the proposed changes to Part 135.

But it is the second reason that causes the biggest problems for air medical providers. The problem is caused by the effects of the requirement to operate under Part 135 whenever medical personnel are on board, in combination with a recently announced (December 23, 2010) proposal by the FAA to impose a new legal interpretation on the crewmember duty rest requirements of FAR 135.263 and 267. The rule establishes a maximum duty day of 14 hours, without exception, for pilots flying under Part 135. It does this by requiring that a pilot be able to look back and see at least 10 consecutive hours of rest in the preceding 24 hours at any time during his duty period, including at the time projected for the completion of his final leg of flight. In helicopter EMS operations, this strict interpretation of the language could lead to situations similar to the following scenarios.

Scenario 1

A pilot is anxiously checking his watch at a back-country ATV accident scene toward the end of his shift. Unanticipated and protracted extrication efforts are underway to free the victim and then medically stabilize her before moving her to the helicopter landing zone for the flight to the hospital. Although his standard scheduled duty period is 12 hours long, he has calculated that the end of his maximum legal duty period will be at 9:00pm local time. He also figures that it will take 6 minutes to carry the patient to the aircraft and that once all are aboard it will require 2 minutes to be ready to take off and 35 minutes to fly to the receiving hospital. So, at 8:17pm (you do the math!), and after alienating everyone involved in the tense extrication process with his exhortations to speed up their efforts, he announces to his medical team that he is departing immediately and that they can either come with him now, or remain with the patient and find some other way to get themselves and their patient off the side of the mountain. He knows that to do otherwise is to risk a violation of FAR 135.267(d) which could result in legal action against his pilot's certificate and hefty fines for his employer.

Scenario 2

A pilot and neonatal specialty team are experiencing prolonged delays in preparing a critically ill newborn infant for transport from a rural hospital to a pediatric specialty hospital 130 miles away. (Anyone who routinely performs neonatal transports can attest to the frequent delays associated with preparing a critically ill newborn for flight.) As in the back-country ATV accident scenario, this flight request came near the end of the shift and it's beginning to look like the pilot will have to abandon the infant to a bumpy 3-hour ambulance ride to avoid a violation of FAR 135.267(d).

FAR 135.263(d) states that

"A flight crewmember is not considered to be assigned flight time in excess of flight time limitations if the flights to which he is assigned normally terminate within the limitations, but due to circumstances beyond the control of the certificate holder or flight crewmember (such as adverse weather conditions), are not at the time of departure expected to reach their destination within the planned flight time."

To avoid scenarios like the two presented above, operators and flight crews have two options when they experience unforeseen patient delays on a transport late in the duty period and there is uncertainty whether the transport can be completed within the 14 hour limitation.

Option 1: If the crew accepted the flight believing that it could be completed within the time allowed, but unanticipated delays due to patient care would now extend the return leg of flight beyond the 14 hour limit, the crew and operator can infer a logical implementation of the language of 135.263(d), above, to include an allowance for a reasonable and  necessary exceedance of the duty time limits in the same manner as for flight time limits (which they wouldn’t need, anyway).

Option 2, and the only option possible under the newly proposed interpretation of the rules, is that the pilot must depart without the patient, as in the scenarios above. The fact that we virtually never hear of patients being abandoned in such circumstances suggests that Option 2 is being exercised in these kinds of circumstances. Although it is not possible to know how this issue is being handled by air medical providers across the country, many "off the record" inquiries that I have made with EMS pilots from a number of different locations have suggested that Option 1 is the option of choice in those rare occasions where truly unanticipated delays have necessitated that the pilot exceed the duty period in order to complete the transport.

An additional hazard that is introduced when a pilot feels pressure to complete a mission within the constraints of a duty period, and where there is no provision whatsoever for any extension, is that the pilot may rush the operation or otherwise cut corners in order to complete the mission on time, which can result in unsafe or even tragic choices on the part of air crews. The greatest disaster in the history of commercial aviation resulted in 583 fatalities when the pilot of a KLM (Dutch Royal Airline) 747 rushed his takeoff from a fog-bound runway and collided with another 747 that had not yet cleared the runway after landing. In the official accident report following the collision between KLM 4805 and Pan Am 1736, the investigators suggested that the Captain's fatal mistake might have been influenced by a desire to leave as soon as possible in order to comply with KLM's duty-time regulations, and before the weather deteriorated further.

An impending duty period limit was also a very likely influence in a fatal medical helicopter crash in California in December 2003.  The NTSB accident investigation docket (LAX04FA076) provides clear indications that the pilot would be feeling pressure to take the quickest course of action possible in order to complete the patient transport within the constraints of his duty period.

The language of FAR 135.263(d) is borrowed almost verbatim from FAR Part 121.471(g) which states that

 "A flight crewmember is not considered to be scheduled for flight time in excess of flight time limitations if the flights to which he is assigned are scheduled and normally terminate within the limitations, but due to circumstances beyond the control of the certificate holder (such as adverse weather conditions), are not at the time of departure expected to reach their destination within the scheduled time."

That language makes more sense in the context of Part 121 operations where the crewmembers are actually assigned specific flights and scheduled for a specific number of flight hours for a duty period. The use of the phrase "flights to which he is assigned" in FAR 135.263(d) is a poor fit for Part 135 air ambulance operations since those flights are rarely scheduled at all, but are conducted on-demand. This is especially true for helicopter air medical transports where the flight team typically learns of a flight request only minutes before takeoff. But, neither the language of 135.263(d) nor 121.471(g) really addresses the need for relief that is occasioned by delays caused by "circumstances beyond the control of the certificate holder...” The "circumstances" that are most often cited in discussions of these rules include late passengers, delays waiting for and loading cargo, or un-forecast adverse weather that might put a flight on hold until departure minimums can be met. In air ambulance operations, the delays are typically patient-related.

None of these delays typically result in any increase in the flight hours required to complete the assigned flights, but such delays could easily result in crewmembers exceeding the rest requirements that dictate the maximum length of a duty period. Yet, the language of both rules clearly provides for exceptions only to flight time limits, with no mention of any exception to the rest requirements that dictate the maximum length of the duty period. The fact that the FAA finds it necessary to officially re-state what the language in the rules already clearly says forces us to speculate whether this action is motivated by abuses by a few operators who have used a liberal interpretation of the the rules as a loophole to extract more duty out of fewer pilots in order to bolster the bottom line.

An additional important consideration in comparing the impact on operational safety that these rules have for Part 121 certificate holders vs. Part 135 air medical transport providers, is the large disparity in actual flight hours flown in a typical duty period by the two types of operations. The economies of scheduled air carrier operations naturally require that those services be provided using the minimum number of pilots commensurate with safety and the requirements of the FAR's. The same is true of Part 135 operations, including air medical transport services. But, the demands of the flying public are such that the pilots of Part 121 operations frequently spend close to the maximum allowable flight hours in the air during each duty period, while air medical pilots typically spend the majority of their duty period in the crew quarters doing a variety of sedentary duty-related tasks, or just reading, or watching TV. Or, they may actually be asleep in bed, since a sleeping area is typically provided for EMS pilots to obtain additional rest while waiting for a flight request; if one occurs at all during any given duty period.

In both of the two hypothetical scenarios presented above, it is very possible that the flight which occurred late in the pilot's shift was his first flight of the duty period, and that it came after 3 or 4, or even 5 or 6 hours asleep in bed[1]. In the "off the record" inquiries mentioned above, the 22 respondents that had exceeded the duty period limits due to patient delays exceeded the 14 hour limit by an average of 42 minutes, with a high of 2.0 hours and a low of six minutes. I found it interesting that, in none of the cases reported to me did the pilot have a need to exceed the 16 your duty day that would be granted to the Part 121 airline pilot by FAR 121.471(c)(1).

But, if there have been occasions of an under-the-counter common-sense approach to handling the issue of patient delays in the past, it is about to be explicitly outlawed by the proposed new legal interpretation. The regulations that limit duty time for pilots are enacted to protect life and limb, but in certain circumstances related to emergency air medical operations, the rules can, and I would assert that they will have just the opposite effect for a patient whose life depends on rapid transport to the medical facility that has the special resources needed to save his or her life.

The disparity between the duty period restrictions on air medical pilots vs. airline pilots is apparent when the effects of the two rules are depicted graphically. The following graphs represent the duty periods allowed by the rules in accordance with the recently proposed legal interpretation. For the sake of illustration, each graph assumes regularly scheduled duty periods of 12 hours beginning at 0700 and 1900 hours local time (the night shift is used for these sample graphs).

The first graph is based on FAR 121.471 (b)(1) and (c)(1), which allows for a maximum of less than 8 flight hours and a maximum 16 hour duty period, followed by a minimum rest period of 10 hours.

FAR Part 121 allows for a maximum 16-hour duty period. Pilot must be able to "look back" at any time and see at least 8 hours of rest within the past 24 hours.

The second graph illustrates how the 10-hour "look back" rest requirement for air ambulance pilots can create a situation where a pilot working a scheduled 12 hour shift can encounter a situation where the proposed interpretation of the regulation might literally result in a death sentence for the patient when the pilot is forced to leave the patient at the accident scene or at the referring hospital. Neither rule makes any provision for exceeding the maximum length of the duty period, based on the "look back" criteria in each case.

FAR Part 135 allows for a maximum 14 hour duty period. Pilot must be able to "look back" at any time and see at least 10 hours of rest within the past 24 hours.


"Special" rule for HEMES operations?

Some of the knowledgeable readers out there are probably thinking, "But, what about FAR 135.271?"  That regulation allows an air ambulance pilot involved in HEMES (helicopter emergency medical evacuation services) operations to reduce his rest period to 8 hours, allowing for up to a 16 hour duty period. While this is true, it comes at a price that relatively few air medical transport programs are willing to pay. Two of the "zingers" in this regulation are 135.271(g) and 135.271(h) (1).

FAR 135.271(g) states that, "No certificate holder may assign any other duties to a flight crewmember during a HEMES assignment." FAA Order 8900.1 further clarifies this restriction with the following language:

"While a flight crewmember is assigned to duty under § 135.271, that person may not be assigned to any other duties. Prohibited duties during a HEMES assignment include, but are not limited to, maintenance test flights, public relations flights, and administrative duties. NOTE:   Inspectors should ensure that operators scheduling under § 135.271 have identified those procedures and policies in their operations manual." (FAA Order 8900.1, Volume 4, Chapter 5, Section 3 Air Ambulance Service Operational Procedures)

But, HEMS providers routinely have a need to use the on-duty crew to assist with maintenance functions when the assigned aircraft experiences any malfunction that requires repositioning, ground run-ups, or short test flights in order to expeditiously return the aircraft to service. It is also very common for the duty crew to reposition the aircraft to locations near the hospital or other base in order to perform outreach training or community education on helicopter air medical operations. Such outreach training is a very important element of air medical services since it trains law enforcement, local health care personnel, and other public and private organizations on the capabilities, limitations, and safety practices that are critical to providing safe and appropriate air medical transport services to the community. These "other duties" are provided by the on-duty crew without any need to extend or adjust either the flight hour limits or the duty period limits specified in FAR 135.271. Their effect on the flight and duty limits of the pilot and crew is precisely the same as a patient transport flight would have, and it seems completely arbitrary to restrict an operator from performing these important functions.

FAR 135.271(h) (1) then adds insult to injury by requiring that:

 "(h) Each pilot must be given a rest period upon completion of the HEMES assignment and prior to being assigned any further duty with the certificate holder of—

(1) At least 12 consecutive hours for an assignment of less than 48 hours."

This language essentially imposes a 12 hour rest period requirement that trumps the 8 hour rest requirement specified in 135.271(d), (as well as the 10 hour requirement of 135.267 (d)), and begs the question of exactly what a "HEMES assignment" is, and to whom FAR 135.271 is intended to apply. The language suggests that it may be intended not so much for dedicated HEMS providers as for operators who may perform air ambulance operations along with other kinds of commercial helicopter flying.

Since air medical operators must declare in their Operations Specifications whether they will schedule their crews under FAR 135.267 or 135.271, the vast majority elect to operate in accordance with 135.267 in order to avoid the onerous restrictions that 135.271 would impose on their crew scheduling and on their maintenance and outreach education activities.

On the other hand . . .

I have to confess that, up to this point, this article has been a one-sided look at the detrimental effects of the proposed new rules from the perspective of the HEMS provider. But, in order to suggest an alternative interpretation or, better yet, a feasible  re-write of these rules, we must also consider the very difficult mandate that the FAA has to publish regulations that insure the safety of aviation operations for all involved without unduly hindering the operations themselves. And, these rules also need to be phrased in language that will preclude the possibility of operators finding ambiguity or loopholes that could allow them to conduct operations or schedule aircrews in a manner that could result in unsafe circumstances due to crewmember fatigue. To address this concern, and since the primary issue at hand is the effect of the rules on air medical operations (and on the outcome for patients), the logical approach to take is to specify parameters for duty period exceptions in the newly proposed changes to FAR Part 135 that will apply to air ambulance operations. At this time, the proposed change to FAR 135.267 applies only to the flight hour limitation and does not address any need to exceed the 14 hour duty day which may arise in exceptional situations due to circumstances beyond the control of the pilot or the operator. In fact, the recommended change to 135.267 is spurious since it purports to require pilots to apply all time flown while medical personnel are on board toward the maximum flight time allowed by 135.267. This is something that air medical programs already do, even though the FAA suggests otherwise in their discussion[WTW1]  of the proposed changes.

It could be argued that the disparity between the minimum 8-hour rest period for airline pilots and the 10-hour rest period required for HEMS pilots is justified by the fact that the Part 121 operations involve two pilots, while the typical EMS helicopter is operated by a single pilot. But, the 14 hour limit applies to 2-pilot Part 135 operations also, and the issue here is not whether two fatigued pilots are better than one, but whether a pilot who has had significant opportunity for rest during his duty period should be constrained from completing a life-saving flight simply because doing so would result in his being airborne after more than 14 hours have elapsed since he clocked in.

To help insure that pilots are fit to fly those late-in-the-shift flights, many air medical transport programs have been proactive in addressing and in monitoring fatigue issues in their operations, with a special focus on night operations. Every pilot in the program where I am employed is enrolled in a comprehensive rest and fatigue management course. The internet-based course, called Z-Coach, educates crewmembers on the effects of fatigue, sleep-debt, and sleep inertia, and then provides individualized guidance on strategies to minimize those effects. In addition to crewmember education, operational control specialists monitor the activities of aircrews throughout the night in order to divert flight requests away from a potentially fatigued crew whenever established parameters are met and alternate resources are available. This additional level of risk management operates as a complement to the formal risk assessment that the pilot performs prior to each flight.

Are we aiming at the right target?

A review of the NTSB accident investigation dockets of medical helicopter accidents reveals that the majority of CFIT accidents occur at night or in bad weather, or in a combination of both. Experts on fatigue would agree that fatigue is necessarily a factor present in virtually all activities that take place on the “backside of the clock”. But, determining how fatigued a crewmember was and how causal fatigue may have been to an accident or mishap is problematic, to say the least; especially if the determination must be made post-mortem!  It should be enough to acknowledge that fatigue is a legitimate concern that requires proactive attention and countermeasures, and then focus on what I believe both pilots and human factors experts will agree is the indisputable primary cause of CFIT accidents: the pilot just didn’t see it coming.

In the Notice of Proposed Rule Making under consideration, the FAA proposes to mandate helicopter terrain awareness and warning system (HTAWS) technology as the universal mitigation for the fact that pilots don’t see well in the dark or in the fog. But, every HEMS pilot with NVG experience that I have talked to has said that the wrong technology has been selected.

In June of 2010, the FAA published a document titled Fact Sheet – Helicopter Emergency Medical Service Safety.  This document states that,

While the FAA is pursuing new rules that support National Transportation Safety Board (NTSB) recommendations, the agency has aggressively promoted significant short-term safety initiatives that do not require rulemaking.”

The Fact Sheet goes on to identify four areas of “immediate focus” that the FAA will consider. One of the FAA’s immediate focus areas identified within the Fact Sheet was to “promote technology such as Night Vision Goggles, terrain awareness and warning systems and radar altimeters.”

But, if the current NPRM is based on the statements in the Fact Sheet, then it is puzzling that the FAA has eliminated any reference to night vision goggles in the proposal. As an enhancement to situational awareness, night vision systems such as NVGs provide the pilot an actual visual representation of terrain, weather, and traffic. When utilized by a properly trained crewmember, NVGs provide vital real world information to the user.

HTAWS technology has proven its effectiveness in the high-altitude IFR environment, but minimal data exists for its use in the low-altitude helicopter environment.  The FAA Fact Sheet states,

“the FAA concluded that there are a number of issues unique to VFR helicopter operations that must be resolved before the FAA considers mandating the use of TAWS in this area.”

On December 17, 2008, the FAA issued Technical Standards Order (TSO) C-194 to standardize the manufacture of HTAWS within the industry. Even with this standardization in place, the benefits of this system to the low-altitude helicopter environment have yet to be conclusively validated or demonstrated.

With regard to NVGs, the FAA has stated their position on the issue in this statement:

“While the FAA encourages use of NVGs where appropriate, they are not a one-size-fits-all magic bullet. Flying at night is not inherently dangerous if rules and procedures are followed. In fact, many operators who do not use NVGs have never had an accident at night.”

But, it is unquestionable that HTAWS is also not a one-size-fits-all magic bullet.  Many operators who do not use HTAWS have never had an accident at night, either. And, the FAA's statement above is certainly arguable: flying at night at the lower altitudes required by HEMS operations is inherently more dangerous than flying those same missions in full daylight. A pilot's unaided visual acuity on a dark night is approximately 20/200, which is legally blind by most accepted definitions. With the current generation of night vision goggles, that acuity is improved to about 20/30 - sometimes a little better, sometimes slightly worse, depending on the level of ambient light.

To suggest that a technology such as HTAWS should be preferred in lieu of NVIS, as this NPRM does, is to ignore the realities of flying a helicopter at relatively low altitudes during periods of darkness, sometimes combined with marginal weather conditions. Using NVG's, the pilot sees the terrain in much the same manner as during daylight flying. Even with the somewhat degraded visual acuity and a slight degradation in depth perception, the pilot is able to perceive all the same visual cues that he enjoys during daylight flight. These include the position, shape, size, and apparent distance to all obstacles while at the same time providing a visual indication of the rate of closure with the obstacles, along with other visual cues of the aircraft's position and motion in 3-dimensional space which correlate with the proprioceptive cues generated by his physical senses. This ability to see in the dark and to fly by visual reference to the environment outside the aircraft reduces pilot workload and stress to a level more like daytime flight and lessens the likelihood of vertigo or spatial disorientation in a way that HTAWS symbology cannot.

In addition, many pilots are not content to wait for the audio warning that indicates that the aircraft is on a collision path with the terrain, so they feel a need to shift their attention to the HTAWS cockpit display to confirm that the course and altitude are safe. On a dark night, and without NVIS, the need to do that may be very frequent, especially if the weather is forcing a pilot to fly at the lower altitudes that are allowed by the proposed new rules. For example, flying on a dark night beneath an overcast ceiling, at an altitude only 500 feet above the terrain or the highest obstacle with only 3 miles of visibility (assuming flight within the local flying area), is not a good time to have to keep shifting attention into the cockpit to see what lies ahead.

Two other issues that make NVIS a superior solution compared to HTAWS, are the ability to see where the ceiling is above the current flight path and altitude, and the ability for the goggle-equipped pilot to turn his head as needed to locate and select an appropriate forced landing area in the event of an engine failure. HTAWS cannot provide either of those very important benefits to a visually unaided pilot.

As an industry, HEMS pilots would agree that flying at night can be safe.  However, night flying does present its own challenges which can, and should be, mitigated using technologies such as HTAWS and NVG's. The FAA recognized this in the current Operating Specification (OpSpec) A-021 Weather Minimums. A-021 places these technologies side-by-side in permitting reduced weather minimums for flight in uncontrolled airspace when either of those devices is in use.

To mandate HTAWS for an entire sector of the commercial helicopter industry while ignoring an alternate technology that is both less costly and more effective, is very puzzling to virtually every air medical helicopter pilot that I have interviewed on these issues. Essentially, it appears that the only time that HTAWS would have an advantage over night vision goggles would be when flying into conditions where the visibility is so degraded due to atmospheric obscuration that the pilot would be unable to see the terrain, even with the aid of NVG's; in other words, when the aircraft has entered inadvertent IMC conditions. We can acknowledge the value of HTAWS technology in such cases, but most HEMS pilots have difficulty in seeing HTAWS as more than a highly recommended technology, while the foregoing discussion of the benefits of NVG's leads us to believe that they should be recognized as the preferred technology for night HEMS operations. HEMS pilots agree with the statement that NVG's are not the silver bullet to cure CFIT accidents. But, with respect to a purely technological mitigation, it is the best bullet.

And since there is no silver bullet, then I believe that a decision to make any technology mandatory should also include some provision for granting exceptions for a HEMS provider where the geography of the area of operation along with other formal conservative rules of operation present in their FAA-approved General Operations Manual would preclude a pilot from accepting or continuing a flight in conditions where CFIT or LOC (loss-of-control) accidents might occur. For many operators, the increased weather requirements required for un-aided flight may be all that is required for them to make the decision to use NVG's.

And if such an exception is granted, then there should be a means for managers and FAA Principal Operations Inspectors (POI's) to insure compliance with the internal rules, minimums, or other standards published in the operator’s GOM or OpSpecs to insure a high level of conservatism regarding minimum flight conditions. An operator granted the exception should be required to comply with the proposed recommendation, included in the NPRM, regarding the installation of LARS (light-weight aircraft recording system) along with a published procedure for monitoring and acting on the flight data gathered. That data will enable managers and POI's to insure compliance with the operating parameters used to justify the exemption.

There are significant efforts currently being conducted in the air medical transport industry to identify the root causes of HEMS accidents and also to identify and mitigate the pressures that may cause aircrews to push the limits of safe operations.[3] In the meantime, the air medical transport community will continue to monitor the rumblings from Washington with a mixture of hope and concern.

[1] In a 2009 survey of 697 HEMS pilots conducted by the National EMS Pilots Association, 94% indicated that their employers provided them with a separate sleeping area in the crew quarters and 70% responded that they typically obtained between 3 and 6 hours of sleep during their night shifts.

[2] Information regarding Z-Coach training is available at http://www.alertness-solutions.com/

[3] The OSI-HEMS research group (Opportunities for Safety Improvement in Helicopter Emergency Medical Services) conducted under the direction of Dr. Ira Blumen of the University of Chicago Air Medical Network, and survey-based research by the National EMS Pilots Association are two examples of such efforts.

 [WTW1]Add remark on CAMTS standards and how the Part 91 tactic can be applied only to the very last leg of the duty period. Then cite data from dockets re: accidents in the Part 91 mode and whether Part 135 would really have made a difference.

Bill Winn is the Safety Officer for Intermountain Life Flight in Salt Lake City and the General Manager for the National EMS Pilots Association. He also serves as a member of the OSI-HEMS research group (see footnote). He served as an instructor pilot and night vision goggle instructor for 18 of his 27 years as a pilot for the US Army. He can be contacted at [email protected].