Flying Helicopters At Night
Helicopter night flight: Flying at night is like flying in a whole new world, ever more-so when you’re doing it in an unstable helicopter.
Night visual operations hold dangers of their own, and there is significant evidence to believe that NVFR is not a visual operation at all. In the unstable platform of a helicopter it can be even worse. Steve Hitchen went in search of answers.
HELICOPTER NIGHT FLIGHT – AN AUSTRALIAN PERSPECTIVE : It should have been a routine mission; it was anything but. At 7.00 pm the Squirrel helicopter lifted off from a location to the east of Lake Eyre with a film crew on board.
It was a very black night; there would have been no discernible horizon. At 1500 feet the pilot started a gentle right turn, but the bank angle increased past gentle, and the aircraft started descending. Thirty-eight seconds later it struck the ground.
The Australian helicopter community was forced into mourning a very well-liked and well-respected pilot and his passengers. That a simple crash like this could be the end of Gary was almost unthinkable. Some operators reacted by raising a glass to the memory of their missing mate, then carrying on business as usual.
Others walked slowly into the hall of mirrors to take a good long look at themselves and their operations, especially their practices of flying visually at night. Some changed rheir ways, others simply stopped flying under Night VFR completely.
“Any flight in an aircraft with reduced visibility weather/light conditions requires total respect …”
It would be another two years before the Australian Transport Safety Bureau (ATSB) released their investigation report, and when it came out, the conclusions surprised very few in the industry: the pilot became spatially disoriented after starting a turn on a night where there was no clear horizon, he had little night flying experience and probably didn’t have the instrument experience to deal wirh the situation.
To compound matters, the helicopter was not fitted with an autopilot and it seems the pilot was distracted trying to reprogram a GPS.
The incident prompted CASA to change the rules for helicopter night VFR. Now, if the flight is to be conducted greater than 30 minutes flying time from an area of significant ground lighting on a night where there is no horizon, the aircraft must have either two pilots on board or an approved autopilot or automatic stabilisation system such as HeliSAS.
But are these measures cures or mitigators? Even within the Australian helicoprer industry there is a feeling that perhaps we should be doing away with NVFR completely and demanding instrument ratings to fly at night. It’s a divisive argument, but one that is being approached from all angles with commonsense and both eyes squarely on safety.
Australian Industry Approach To Helicopter Night Flying
Ray Cronin is the founder and Managing Director of Kestrel Aviation in Mangalore, Victoria, one of Australia’s most respected helicopter training schools. Cronin is also the Vice President of the Australian Helicopter Industry Association (AHIA), a peak body that looks after the interests of Australia’s rotary operators.
AHIA’s position on the matter is that at the moment CASA has the regulations in place to keep pilots safe at night… provided they play the game strictly in accordance with the rules.
“AHIA supports the position that if the appropriate guidelines established within the regulations are applied and respected by those operating helicopters at night under the NVFR rules, adequate levels of safety are present,” Cronin says.
“As technology improves, as has been evidenced by the advancements in navigation systems, the work load for pilots in limited visual conditions has been reduced in recent years. “Further enhancements in night vision systems afford a new level of visual supplement; however, they are not currently available or affordable to the private sector of the industry.”
Visual flying at night has challenges that simply aren’t there during the day, even in an aeroplane. It all comes down to the pilot’s ability to relate the aircraft’s attitude and bank angle to the horizon. It is the major point of reference, and without it, visual flight is practically impossible.
Even on the best of moon-lit nights, the horizon can be marked by nothing more than a region of variation in shades of black. Add to that some unexpected clouds that obscure the horizon and an un-trained pilot is suddenly in a world they really don’t want to be, and the options for getting out of it are limited.
Other cues such as ground-lighting planes can be invaluable, but they are found only in and immediately around towns, and over water almost not at all. “Any flight in aircraft in reduced visibility requires respect as margins are reduced and pilots must be trained and maintain recency with their skills sets to operate safely,” Cronin says.
“This includes the requirements to respect the published or calculated lowest safe altitude and alternate minimal provisions. Visual information can vary significantly depending on the urban surroundings verses remote black-hole environments and pilots that transition from one extreme to the other must seek support and training, particularly from urban luminosity to remote outback operations.”
“The AHIA does caution against the temptation of operating in limited visibility such as night operations without the appropriate qualifications and serviceable equipment. The loss of life in these arenas in recent years is regrettable and needs to be a area of educational focus for us all to ensure that greater awareness of the dangers are communicated to all helicopter pilots.”
In 2012, the ATSB completed a report into accidents occurring under NVFR and came up with some staggering statistics including:
in the 20 years between 1993 and 2012 there were 36 accidents at night
27 of those were fatal
58 people died
a third of the accidents were in helicopters
nearly all occurred on dark nights.
“In very dark conditions, VMC essentially equates to IMC in terms of available external visual information,” the report states. “Pilots need to reassess their night flying experience, recency and proficiency before every night flight, taking into account the level of instrument flying required based on the level of darkness.”
And there are dragons hidden in the darkness in the form of clouds. Flying visually by day, a pilot can take action to avoid cloud before they plunge into it; at night that’s an absent luxury because the cloud arrives on the nose unannounced. By the time the pilot knows there’s cloud around they’re already in it.
Add to that the customary twin demons of night flight: somatogravic (acceleration feeling like a pitch-up) and somatogyral (a lack of awareness that a bank angle is increasing) illusions and the pilot needs to be on their game to keep in the air safely.
Helicopter Night Flight Training: Asking the experts
Becker Helicopters used to be a typical helicopter flight training operation on the Sunshine Coast that operated a Bell 47, R22s, TH55 s and a Squirrel. Under the guidance of Directors Mike Becker (Chief Pilot) and Jan Becker (CEO and also a helicopter pilot), they trained approximately 25 new CPL-Hs every year.
In 2008 they signed their first of several international training contracts, which signaled the development of Becker Helicopters Pilot Academy into one of the largest helicopter flight schools in the Southern Hemisphere.
Now operating a fleet of 15 IFRand NVG Bell 206BIII Jet Rangers and four Off Planet simulators (another company owned by the Beckers) they dispatch over 250 training sorties every week and log around 4000 hours of night training annually. Part of their growth and success has been the team of civil and military pilot instructors and the invaluable input they have bought to the company.
These include Senior IFR and Night Vision Goggles Instructor Kim Jorgensen, Flight Training Director Scott Summers, Deputy Chief Pilot Fergus Ponder and an experienced team of instructors, many of whom have significant IFR, NVFR and NVG instruction time.
Jorgensen, a former commanding officer of the Army School of Aviation at Oakey, has among his credentials a career flying Hueys, Kiowas, Blackhawks and Tiger ARHs, and Summers is a former lead instructor on Blackhawks for Specials Operations in the ADF; both have extensive night experience, with not all of it done behind Australia’s secure borders.
As army pilots they have logged many hours in the dead of night and are aware of what can befall a helicopter flying at night. Jorgensen firmly believes that night visual flying in helicopters needs to be put under a very critical microscope.
“Right now we need to understand why night VFR was allowed,” he says. “It was created to aid pilots who were caught short at the end of the day to be able to get home in the dark safely. It was never intended for the expanded use that it has now.
“It used to be called a Class 4 Instrument Rating. Realistically, people are not night V FR flying; they’re flying with reference to the instruments for attitude and navigation without an instrument rating. In my opinion there is no real safety point. You should be either IFR, or you shouldn’t be up there at all.”
With that said, not having the NVFR option is not a luxury the helicopter industry has; there are some critical missions that just have to be flown.
“The biggest problem you have is that in a helicopter you have an inherently unstable platform,” Jorgensen said. “An aeroplane in general flight is reasonably stable; you can trim it out and you have some capability to cruise at night.
“In a helicopter, the problem is predominantly the unstable platform. When you’re above 40 or 60 knots in a helicopter, you’ve got an aeroplane. When you’re below that speed, the helicopter requires different skills. “It’s the transition from taking off and getting to fly-away speed that is the most difficult in a helicopter.
It’s very difficult if all you can see around you is black and there’s no horizon. And if you’ve had minimal exposure to an attitude indicator, then of course you’re going to have problems. In a helicopter take-offs and landings have to be done visually, often into tight landing zones under very trying circumstances with limited lighting.
“Most people don’t realise that its not unusual for a commercial helicopter pilot to have never seen an attitude indicator or an artificial horizon until after they get their CPL and start working for an organisation that may have a requirement for helicopter night flight.
“Now that you are required to do instrument training as part of your commercial pilot licence, it’s a different story and a good step forward for future competencies in flying with reference to the instruments.”
The majority of Australia’s commercial helicopter pilots have the luxury of going home at night and not having to worry about the black all around, but for certain operations, night visual flying is part and parcel of what they do. Law enforcement, search and rescue, helicopter emergency medical services (HEMS), marine pilot transfer and some agricultural operators all accept the risks of night flight as part of what they do.
Although many will operate on instruments, there are no non-precision approaches to road sides or forest clearings, so the approach is often made in darkness with only some well-laid ground lights to bring them in.
Kim Jorgensen; “Imagine you’re an EMS pilots and you’re going to land at a crash site that’s been lit by police cars or something, or you may be an operator that’s been working a bit more remotely and there’s star aids, or T-aids or Y-aids that have been set up appropriately. That’s where life starts to get a little bit more interesting.”
On a black night helicopter pilots can find themselves approaching a landing zone with as little as two twinkling lights to guide them in, all the time hoping the people on the ground have got them in the right places to bring the helicopter in without scraping the paint on pine trees or running into a wire. It’s enough to make you wish you were home in bed.
What’s to be done?
“When the Twin Squirrel crashed at Lake Eyre it hit home to all the helicopter industry,” Jorgensen recalls ruefully. “It was tragic that such an experienced aviator would be lost in such circumstances, but what it reminded us was that you can’t become complacent.”
Becker Helicopters NVG team made changes after the Lake Eyre crash, putting emphasis on instrument flying skills, a sterile cockpit, pilots being familiar with aircraft systems and procedures, the risk of illusions at night and human factors, and tying it all in together in an attempt to mitigate risk in their night operations.
All of Becker Helicopters’ NVG instructors hold IFR instructor ratings. This, they say, is a major mitigation strategy. Kim Jorgensen: “Having instrument skills, being able to get onto the clocks when you need to and having the training to recover when you cannot see the horizon is paramount to maintaining the safety of the aircraft and crew”.
So why would the industry not simply delete the NVFR rating for all aircraft and accept only IFR at night? According to Jorgensen, that is simply not an option for the industry.
ABOVE : Becker Helicopters has a fleet at 15 Jet Rangers doing up to 250 training sorties every week.
“In the helicopter world, that’s not viable. It’s very, very cost-prohibitive as all IFR helicopters must have an autopilot or stability system and to retrofit and install this on a helicopter would cost hundreds of thousands of dollars. If you make it pure IFR, the general aviation industry would suffer in that area.
“Yes, we will have fewer night VFR pilots, and we will have people that will have to undergo a full instrument test and they will be forced every year to have a renewal, but what is the cost versus risk benefit?
“If we could make instrument ratings more accessible, then yes, I agree 100%. An instrument rating is the number one risk mitigator of everything, and that includes both night VFR and operations using night vision imaging systems, but the reality of that ever happening is simply not there.”
Goggle-eyed at night
In an ideal world, helicopter pilots would be fitted with eyes like cats that can see in the dark, but without that, genuine night VFR conditions probably don’t exist; even in the best of conditions there are still illusions to be dealt with. Technology, however, will give the closest thing possible; night vision goggles (NVGs).
“In an ideal world helicopter pilots would be fitted with eyes like cats …”
Until recently, NVG’s were the exclusive privilege of the military with both foot soldiers and aviators using them to great effect in night missions. Indeed, it has been said that military helicopter pilots will scream and run at the suggestion of flying VFR at night without them. Yet, their civilian counterparts are doing it regularly.
Right now, CASA will allow only certain operators to use NVGs, and even then on only SAR, law enforcement aerial fire-fighting, HEMS, marine pilot transfer and NVG training flights. If you are simply doing a night flight for aerial work or private flying CASA says “no” to you using NVGs.
But even if they were to change their minds (and that is a real possibility) NVG’s are still not the perfect solution.
“Night vision goggles don’t turn day into night,” Jorgensen stresses, “and if anyone says they do, they haven’t ever flown with NVGs.” Most NVG’s work by detecting and amplifying available light.
Buildings emit low levels of light; humans and animals slightly more. Photons from that light enter the goggles and are converted into electrons, multiplied significantly, and cast onto a phosphor screen. The eyes see what is on that screen.
No, it’s not daylight; it’s a whole new world of grainy green that is remarkably accurate to what would be before you had the sun not gone down.
How good are they? In a demonstration for Australian Flying, Kim Jorgensen landed a Bell 206 Jet Ranger in an unlit, tennis-court-sized clearing on a very black night in the middle of Queensland’s Bribie Island. He even waited for the wallabies to clear out first. He saw everything through NVGs. Without them, there was nothing but darkness in front of the Jet Ranger.
So if that is possible, why are they not the perfect solution? Because a pilot needs a lot of training and experience with them to understand what the goggles are showing them. Is that light-green smear a road or a river? What do power-lines look like in NVGs? (Night Vision Goggles) How is the brain interpreting the two-dimensional image projected onto the two small screens as opposed to what is really out there?
Currently, an NVG rating requires a minimum of five hours training, but most of the industry-and Becker Helicopters in particular-are finding that 15 hours is more like the time needed to be competent and safe. It is, apparently, very easy to use them wrong.
“The first flight with NVG’s is a bit of a jaw-dropper,” Jorgensen points out, “especially if the pilot has been night VFR flying. If it’s a bright night, the NVG’s will nearly burn your eyeballs out as they have so much light to work with. If it’s a dark night there is still enough light to get a good image but there is also the realisation that ‘if it’s like this now, what will it be like with a little bit of moon?’
“When I take them lower and closer to the ground, the trainee starts to get a feel for the height-or lack of height-they start to realise that this could be dangerous if used incorrectly.”
Many instructors find once they teach pilots NVGs, the biggest issue is then trying to get them to fly at night without NVGs.
T h e second issue is that NVG’s can fail, and if that happens in the dead of the pitch-black night, your only recourse is to instruments. Yes, it’s a paradox, but to use NVG s safely you have to be proficient on your instrument flying as well. To not be so is to have no back-up plan.
Fun for all?
The strength of NVG’s is not so much a means to control a helicopter at night, but the ability to see the ground to carry out a mission; to search for a downed aeroplane, or someone lost in an alpine region at night. They will show you trees swaying so you know what the wind low down is doing, they will let you follow a road or track … or a stolen car.
And then there’s the engine-failure scenario. An auto-rotation to the ground at night is every bit as fraught as a fixed-wing forced landing. NVG s give you a better chance and they give you the opportunity to pick a spot and put the aircraft on the ground successfully.
It’s for the utility value that CASA has allowed emergency services to use NVGs, but not private or commercial helicopter operations. Becker Helicopters sees the value in professionally trained NVG pilots flying in all operations, and views them as the way of the future.
“I think what’s going to happen is that night VFR will slowly be replaced by NVGs. There will be a heavier emphasis on IFR, and a lot of emphasis on night vision goggles.
“Try and find a military pilot that goes night VFR. They’ll only use it to recover in the event of a goggle failure, and even if they lost one tube, they’d still use the goggles.”
But even so, properly functioning NVGs have problems that may limit their value to general aviation: they’re heavy and have to be connected to a helmet, they cost around $15-20,000 per set, they can’t operate in total blackness, aircraft navigation lights appear to be the same colour so you can’t tell what direction another aircraft is going and they have issues with low-contrast.
All of these may be barriers to NVG s becoming common in general aviation, but it will take only one flight with them on to realise that they can be life-savers, and in that situation you won’t be giving much thought to the drawbacks.
There are several factors that brought down the Squirrel at Lake Eyre, but the unmistakable conclusion is that had the flight been conducted on instruments or with NVGs, it may well have turned out to be what it should always have been; routine.
Instead it catalysed the helicopter industry into examining their own positions when it comes to night VFR operations. Clearly, there was a lot to learn, and different operators looked at it from different angles.
Two factors came into sharp focus: proper training and awareness is critical if you want to fly safely at night, and flaunting the rules is courting disaster, trained or not.