These notes are to assist Location Managers on shoots when helicopters are planned to be involved.
Initially it is important that you understand how helicopters work and what the Pilot and legislators are considering during their operation.
Helicopter operations are a minefield of "yes but not in this case". The following text is to give a broad brush understanding; check with your helicopter supplier.
What's the difference between a twin engined or single engined helicopter (Apart from one engine)?
Engine failure in a single engined helicopter means you will enter a descent! Thus for the carriage of paying passengers, there is no night flying, very limited overwater flight and high minimum heights over built up areas.
You might be surprised that with most light twin engined helicopters in the UK, if one of the two engines stops, you might not be able to continue flight. It depends on weight and speed and air temperature. As most filming is at high weights, an engine failure below typically 40kts will mean the aircraft will not be able to maintain height.
High temperature reduces the air's density i.e. less for the rotor system to bite on. The onboard loads that might be possible at dawn may be much reduced in the heat at midday in summer.
Twin engined helicopters can operate at night (with a number of restrictions) over-water and down to lower levels over built up areas (subject to specific CAA dispensations)
If the engine stops they crash and burn
There are 1500 professional helicopter Pilots in the UK, if this was true there would be probably only 5 who would still fly them (and they are all on "care in the community schemes" ).
The fact is that the rotor system has two properties, it can be a powered fan or a wind driven windmill.
When the engine stops it automatically de-couples from the main/tail rotor drive.
The helicopter descends and the air's relative up-flow drives the rotors providing a percentage of lift. Throughout, the Pilot has full control and can turn, accelerate, slow down, everything except a sustained climb.
The helicopter is gliding - in Auto Rotation (like a Sycamore leaf).
Having selected and positioned into the most suitable nice flat surface he slows the helicopter by raising the nose which actually has the effect of speeding the rotors up, gently pushes forward to level the aircraft.
Then slowly increases the pitch of the main rotor whilst the increased drag slows the blades down, it increases lift thus cushions the aircraft's descent onto the ground, normally with a short landing skid to a halt along the ground .. Phew!
The basic profile is shown below, when you learn to fly you practice this a great deal. Professional Pilots are examined on this and other emergency procedures every 6 months
There are actually a number of different profiles that can be used from different heights and airspeeds.
For you as a location manager if your location is in serious hills such as Snowdonia, the chances of pulling off the procedure above is fine, until you come to the skid bit.
As helicopters normally have the engines mounted high up they are not ideal as toboggans and will tip over, which is very tedious and frequently fatal.
As you can imagine landing in forests can be also most disappointing.
So all that helicopter pilots are interested in throughout the flight is "if everything quits, where do I have somewhere to land?"
Avoid Curve
In the opinion of the helicopter designers and test pilots height/speed combinations placing the helicopter within the shaded areas means the helicopter is unlikely to be able to land without damage, from light to possibly fatal.
Therefore next time you see (in this case a Jetranger) hovering at 200 ft with no airspeed don't think what a wonderful pilot, think what a pratt! (Twin engined helicopters can do this but have other considerations).
The important thing for you to remember is what a helicopter can do, is not always what it should do.
However, clearly parameters change if you're getting shot at!
Where can they land?
Any suitable site providing you have the land owners permission.
What is a suitable site?
When looking for suitable sites to land a helicopter it is important to understand the problems faced by the helicopter supplier.
The rules for private flight are far more relaxed than for public transport work. Currently in the UK, all film work, including recceing, is conducted under effectively CAA Public Transport rules.
Therefore it is not unusual to have a location such as a Hotel where helicopters regularly fly into privately but the landing/take off area distances prohibit Public Transport work!
The example below is typical, the helicopter could fly in but not legally undertake Public transport.
If those trees are 50 ft high, look at the Avoid Curve Graph, with no airspeed possible due to the clearing, and consider for yourself if it is even sensible to go into this site.
Note: If a site such as this is needed for an action shot, fine but as you now understand it affects what type of helicopter is selected to be used. The key is, don't let the production spring this type of shot on an unsuspecting pilot on the day.
There are some Pilots who will take calculated risks as does a stuntman, fine. However as a comparison you work in films and TV, would you volunteer on a shoot to do a stunt that in your knowledgeable opinion might paralise or kill you (and to add insult, for no extra money)? I think not!
That's what is often asked in innocence and ignorance of pilots at short notice.
Public Transport rules
The rules covering pubic transport flying are complex but basically break down to the key fact that as Pilot, you have to plan your flight path so that if you loose power, you can "crash nicely". This translates into the fact that you can destroy the helicopter but must not injure the passengers.
The key assessment is that there must be an unobstructed clear distance of a minimum 100 metres x 30 metres then a further 200-300 metres containing nothing more than "frangible" items.
The best way to assess a frangible item is to assume if you were in a heavy four wheel drive car traveling at speed, is there any item that you could not crash through.
The actual landing area can be quite small, approximately the size of two tennis courts, but it is the clear area and its surrounds that is important.
Take pictures, make a sketch with honest dimensions and check with the helicopter supplier. Also while you're there, check if there is any livestock, hospitals, old peoples homes nearby; if there is, tell the helicopter company.
What surfaces can helicopters land on?
Ideally any hard level surface, free from stones and other loose items. Soft ground is not good particularly for helicopters with wheels.
Helicopters are surprisingly intolerant of slopping ground, the maximum being between 7° and 10°. The trick is, if you think that there's more than a hint of a slope its normally too much.
Additionally, when fixing camera mounts, balancing whilst on a slope is very difficult.
For a gentle hillside the way to assess the angle is to place an item such as a case in the intended landing place and then pace 60 metres up the hill, turn and look back to your marker. Assess how many feet you are up or down from the marker and this will be the number of degrees of the slope, i.e. 3ft above equals a 3° slope.
Landing on waste ground is not good news, particularly in dry weather. It coats the camera equipment with dust which will not blow away in flight.
One of the worst enemies of the helicopter is plastic bags and rubbish. They wrap them selves round the main or tail rotor blades or board fly and may injure both the crew and cause catastrophic events; this is no joke, take any rubbish very seriously.
Where can we work ?
This is actually a big subject with lots of trappy bits that can bite you as a location manager, as quite often an aerial shot has not been finally decided upon or you're amongst the first to get employed.
Around the UK there are more restricted flying areas which are perfectly possible to drive across and in many cases very attractive, such as Salisbury Plains, but are completely impossible to get permission to fly in on the day.
Check before you go recceing. Charts are available but they're a bit daunting if you are not used to them, with danger areas, prohibited areas, permanently active, sometimes active etc etc If you want to hold your nose and go for it they are available from Transair by credit card. You need either a quarter or a half million scale chart.
To save embarrassment of showing a Director a location he cannot use, have it checked with us as we have all the up to date changes and new contact numbers in the event of a question.
Even small aerodromes have an aerodrome air traffic zone around them. Trying to work avoiding training Pilots is not good.
Military Airfields have larger Military Air Traffic Zones (MATZ). Aviation people love abbreviations (APLA). These actually don't have any legal status but they often have fast jets at low level, so working with their air traffic control is sensible! It is quite possible that even if you have made multi visits to your location, nothing was flying, but it will on the shoot-day!
Some airfields have Instrument Landing Systems; in a perfect world the approach slope is 300 ft in just over a mile, therefore at 3 miles the aircraft should be at 900 ft on the centerline unless they are instrument training where they could be anywhere!
Last but certainly not least, temporarily restricted airspace such as Airshows and can be a real pain. Even the Red Arrows do shows over sites that are not necessarily airfields. The royal family are using helicopters far more now, when they do, they have the aeronaughtical equivalent of a three dimensional empty motorway around them. These routes are pre published but do change. This is called Purple airspace a colour favoured by the Roman Empire!
When recceing by helicopter how many people can travel ?
The glib answer is "as few as possible".
In a Jet Ranger one person equals one hour of fuel. When the aircraft only has 3 hours total fuel, this cuts down the airborne time hugely, as after l.5 hours flight you are going to have to refuel again.
Additionally, it is not pleasant to spend a long day airborne when sitting in the middle of the rear bench seat as you can see very little.
Do we need overnight security?
Normally yes, get one lined up, but with a pre agreed late confirmation.
It is essential to have overnight security with any helicopter you work with. There is a tendency for passers by to touch and they can unintentionally damage the aircraft quite severely.
We normally recommend that a security guard is accompanied by a dog, primarily because even if the guard goes to sleep the dog does not.
CANP
CANP anther anachronym! It means Civil Aviation Notification Procedure. The system allows the military to be notified of flying taking place in a specific area to allow them to avoid us. In reality, it seems to often turn into a target, because filming to military chaps is sex drugs and rock and roll and they want to look, even if at 450kts. In reality it is better to get your notification for all the right health and safety reasons.
Do helicopters damage?
This is a frequently asked question from location owners. Regarding landing marks, a skidded helicopter will cause no more of an indent than would be made by a car. Even when using cricket pitches it is normal to approach to the centre and hover then taxi to the boundary, thus causing no problems.
Beware of Caterers awnings and tables, helicopter down wash is not that fast but there's a lot of it and can get funneled between buildings.
Refuelling
Be aware that any refuelling bowser is heavy and quite frequently the hoses are not that long. Moving fuel by jerry can is not an option; in a Twin Squirrel helicopter, a 5 gallon jerry can is used in 4 mins.
Helicopter fuel is normally AVTUR, a version of paraffin and is quite stable compared to petrol but no smoking is essential.
AVTUR spillage's severely damage grass.
Security is required against tampering.
Who do I need to inform?
Do not contact the CAA. The helicopter company will do so if required.
Do inform all the standard locals, but do be aware of farmers, particularly chicken farmers as when hens are frightened they go off lay and he losses a days production, (so he's not best pleased!) and any horses.
Do inform the local Police before and then again on the day. (The information never gets through the system and all you get is that "we don't mind but we should have been told, now where's the caterers"). To locals a helicopter landing in an odd place has either crashed or is delivering drugs.
Do I need special fire and medical cover?
Fire and medical cover is not required if there is less than 10 movements in one location in a day. A movement is a take off or a landing. That is the rule but clearly it's a good idea to have as much cover as is viable particularly medical. St John ambulance are excellent and very cheap but if you book them, then in the event of an incident it could be messy and an aspirin or sticking plaster nurse is not really relevant.
Are all helicopter companies reliable?
Not in the slightest, are all production companies the same? Some are good, some not, be suspicious, email everthing, provide as much information as possible as early as possible because if there's a standoff, 99:1 your employers are going to believe the highly qualified bloke with the gold bars rather than you.
This type of graph is a typical example for single engined helicopters. As you can see speed is indicated along the bottom, height on the left hand side.
