I've recently been watching an interesting documentary on helicopter paramedic teams. As you all probably know, their job consists of a lot of sitting around doing nothing before a scramble and then a short (or not-so-short) flight out to the middle of nowhere and back again. On the (UK) documentaries I've seen, the aircraft are usually based at reasonably large commercial airports, physically located close to the fixed-wing runways.

In order to find the guy lying injured in the field and help him out of asystole, they have to rapidly launch from a presumably busy airspace, and get there ten minutes ago. Do airports have procedures that allow them to always assume an "exit route" is always okay, under some ceiling? Do they have to get take off clearance as other private aircraft would? I understand that they get given priority ATC clearance when in controlled airspace, but quite often their target call-to-takeoff times are less than two minutes, and it seems unlikely that the nearby 777 on FA would be done that quickly.

What happens if it's not possible to be VFR entirely on route? I have seen cases reported where difficulties are encountered due to fading light halfway through treating a patient -- meaning that the pilot is worried he can't take off again. It seems rather odd that, if a pilot was able to land in a field comfortably with good visibility, he can't ask for a route to be cleared, file a flight plan, and go to hospital IFR.

For that matter, how do police helicopters chase the bad guys at night in zero visibility?

Disclaimer: I've never set foot in a helicopter in my life, but have a single-digit number of hours in light aircraft -- sick people are more my forte.

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    $\begingroup$ I don't know much, but I can tell you that some police helicopter pilots fly with night vision goggles at night. $\endgroup$ Mar 4, 2015 at 0:22
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    $\begingroup$ As an aside: Police helicopters generally don't chase bad guys in ZERO visibility - but at night they can be flying in VFR while using heat-sensitive cameras to track the baddies. $\endgroup$
    – Jon Story
    Mar 4, 2015 at 15:41
  • $\begingroup$ In my experience as one of the people on the ground summoning such helicopters, they simply do not fly in IFR conditions. Based on only one example I can recall, if conditions deteriorate while they're on the ground, they stay grounded and the medical personnel go with the patient by ambulance while the pilot stays with the helicopter at the scene. However, I'm sure these are all policies that will vary from one service to another. $\endgroup$ Jan 19, 2020 at 23:21

4 Answers 4


If the helicopter is operating at an airport, it needs clearance like a regular flight, otherwise it would be a very dangerous situation for the helicopter and any other traffic in the area. Usually the ATC will give priority to the emergency helicopter (as much as possible), so it will leave the area without delay.

Regarding the weather conditions, there are two aspects that need to be considered:

  • The regulations allow emergency helicopters to fly VFR below VMC minima (this is true in Europe, I have no idea about FAA). So, an emergency helicopter, can continue VFR with visibility down to 1km, or even 800 meters for short periods of time.
  • If the helicopter is IFR equipped and the pilot(s) IFR rated, it can switch to IFR if necessary. On the way to the accident site this might not be very useful if the weather will not allow safe descent and switch to VFR, but on the way back to the airport/hospital, it can be very useful, provided the landing site has some kind of IFR procedure. Again, ATC will usually offer full cooperation in all this switching of plans and flight rules.
  • $\begingroup$ In the US, in controlled-airspace surface areas (i.e. not 10+ miles from an airport), both fixed- and rotary-wing aircraft may be granted a "Special VFR" clearance. This allows them to operate when the ceiling is below 1000' AGL and/or flight visibility is less than 3SM. For fixed-wing operations, flight visibility must be at least 1SM. Rotary-wing aircraft do not have this requirement. $\endgroup$
    – randomhead
    Oct 26, 2021 at 5:32

I dont fly rotorcraft but I do interact with emergency choppers in 2 ways. I'll speak form what I have seen, I am in Philadelphia (PA, USA) so all my experience is with the procedures around here (FAA).

Storage And Takeoff:
I am currently doing my training at Northeast Philadelphia Airport (KPNE) where the local police and news choppers are stored (I think the medical choppers are there as well but I have yet to see them there). I have seen them depart often and generally they can get in the air and get out of the way so fast they don't interrupt normal aircraft traffic.

I have, on a few occasions, been instructed to extend my downwind for one of them to land or take off but again they are out so fast it's almost a non-issue. Keep in mind that KPNE is not Philly international so I don't know what its like at other cities and if they hold traffic for them. I would think they try to store the choppers at smaller airports near the city for this reason. Most major cities have a few airports anyway.

Landing At The Hospital:
My apartment happens to be next to one of the major hospitals in Philadelphia and I have the pleasure of looking right at the pad on the roof from my window. That being said I also have the "pleasure" of watching them practice and make approaches at the hospital. I can confirm that they have made landings (and frequently at that) in IFR conditions or even what seems below IFR minimums.

I would say in the time frame I am home (after 5pm every day) they make on average one landing every other day or more. If the weather is good, they will try and get more in, I would assume these are practice but I can't see the doors of the chopper so I can't be sure.

Bottom line is in my area the rescue choppers do fly IFR. I'll try and capture a picture today (it's very cloudy) if they are on approach.


Getting a clearance

If operating at a controlled aerodrome, a rescue helicopter needs a clearance just like any other aircraft. Given the quick response required, the crew will not be able to file a flightplan before the flight, so ATC does not know when a rescue flight is coming, or where it is going.

Where I work, the helicopter base has a panel with 4 buttons at the entrance to the hangar: North, East, South and West. When the helicopter is scrambled and the crew members are running to the hangar, they will press the button corresponding to the departure direction. This gives us a warning in the tower. Typically, from the time we get the warning and until they are ready for liftoff is somewhere between 2 and 5 minutes, and since we (roughly) know they departure direction, we can start planning other traffic around it (i.e. if they are departing to the north, they need to cross the runway - to the east or west they will fly through the approach path (depending on runway in use) - to the south, normally not an issue). I imagine other airport have similar systems in place, but even if we just have to wait for the pilot to call on the radio (sometimes they forget to press the button), that still gives us 30-60 seconds of notice before they are ready to go. ATC is used to dealing with rapidly changing and unexpected situations, and this is no different.

The rescue helicopter will almost always depart VFR, which is quite easy to handle from an ATC point of view. In case of bad weather (reduced visibility or low ceiling) we might need to provide additional separation to other traffic. Rescue helicopters have priority over almost all other air traffic (except emergencies and maybe a few other obscure cases), which means that we will always clear the rescue helicopter to fly in a straight line to where they need to go - regardless of normal procedures, noise abatement and other traffic. If another aircraft is in the way of the helicopter, we move that other aircaft. In your example with a 777 on final approach, it will be told to cancel approach/go around to make way for the helicopter. I have personally done so on more than one occasion, and when you tell the jet crew the reason, they don't mind at all. It's just like making room for an ambulance on the road.


As mentioned above, rescue helicopters will normally fly VFR. It's not that they can't fly IFR, but the problem is that landing at the rescue site (outside of an airport) cannot be done IFR, so it doesn't really make sense to fly there IFR. In case of low ceiling (clouds) forcing the crew to go IFR, they will have a problem when coming in to land: it will be impossible for them to descend VFR below the clouds. The way they typically deal with this is to fly to a nearby airport when an instrument approach (ILS etc.), fly that approach to below the clouds and then go VFR and continue to the rescue site. This detour is obviously not desired in a situations where seconds can mean the differences between life and death.

Rescue helicopters do have lower VMC minima than other flights, allowing them to fly VFR even when other flights would not be allowed due to visibility or ceiling. The advantage of helicopters is that they can fly really slow, so low visibility is not that much of an issue.

They do sometimes pick up IFR after having picked up a patient headed for the hospital, since some hospitals do have IFR approach procedures, or when returning to base after a mission. In my experience though, they will almost always fly VFR and if the weather is too poor to allow VFR, they will normally not be scrambled at all (since they would not be able to land at the rescue site). The exception is terrain following radar equipped radar helicopters that also have collision avoidance.

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    $\begingroup$ A good example of not flying in IFR conditions was at the F1 Eifle Grand Prix this fall (October?) at the Nurburgring in Germany. There were low clouds and rain off and on all day Friday. While conditions weren't bad at the track and the Medivac helicopter could have easily flown (the TV helicopter was up for most of the day), both practice sessions were cancelled because the helicopter could not land at the designated hospital because they were under IMC and they don't t have an IFR approach. $\endgroup$
    – FreeMan
    Jan 12, 2021 at 16:47

I don't fly rotocraft, but I can tell you if the airport is of any size they have to get a clearance unless they want to be turned into a hood ornament.

If the helicopter is pre-flighted and ready to go, it only takes few seconds to get a clearance, so it will not normally cause a delay.

Concerning IFR Flight: rotocraft require special equipment to fly IFR and it is much, much more dangerous than flying aircraft IFR because you are landing off field. Each operator and pilot have different policies, but in general police helicopters will rarely if ever fly IFR, and medivacs will only fly IFR if they judge it safe.

Note that flying at night is not the same thing as flying IFR. If the sky is clear it is VFR, even if it is night.

Being on a medivac crew is the most dangerous regular job in the United States and hundreds have died doing it.

  • $\begingroup$ In the UK at least, police ops are frequently IFR. Any aircraft will only fly IFR if they judge it to be safe. $\endgroup$
    – Simon
    Mar 4, 2015 at 9:27
  • $\begingroup$ Related to IFR, I know that more than a few Formula 1 races (and, presumably, those in other race series), have been delayed because they require a helo for medical emergencies, and the weather is too bad to fly the chopper. $\endgroup$
    – FreeMan
    Mar 4, 2015 at 13:06
  • $\begingroup$ @FreeMan That's true, and varies a lot with jurisdiction, but being too bad to fly does not imply can't fly IFR. $\endgroup$
    – Simon
    Mar 4, 2015 at 18:32

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