Flight Rule Changes

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Flights containing a change of flight rules are mainly used to fly to and from airports, which usually do or cannot handle IFR flights.

from IFR to VFR ("IFR-Cancellation")

IFR flights can only cancelled and continued under VFR under following requirements:

  1. VMC conditions need to prevail in the respective airspace
  2. If the flight should be continued in airspace class C or D respectively airspace class E during the night after the flight rule change, a CVFR- or NVFR clearance is required
  3. The IFR cancellation is only to be executed above the MRVA, or on published IFR procedures if cleared below the MRVA


The following is an example for a flightrule change in airspace class E:

Pilot:    Wien Radar, OEAUT, request cancel IFR. 
LOWW_APP: OEAUT, IFR cancelled at 1230z, Squawk VFR, frequency change approved.
Pilot:    IFR cancelled at 1230z, squawking VFR, frequency change approved, OEAUT. 

If the plane is still in controlled airspace when issuing its request for IFR cancellations, either an order to leave the controlled airspace or a clearance to continue the flight under VFR in controlled airspace is required. Usually, controllers and pilots come to an agreement about the pilot's plans after the cancellation, and the controllers try to fulfil the pilot's wishes - for example:

Example for flight rule change in airspace class C:

Pilot:    Wien Radar, OEAUT, request cancel IFR.
LOWW_APP: OEAUT, report intentions after IFR cancellation.
Pilot:    request to decend below Airspace C direct Sollenau VOR, OEAUT.
LOWW_APP: OEAUT, approved as requested, proceed direct to Sollenau VOR, IFR cancelled at 1230z.
Pilot:    Proceed direct to Sollenau VOR, IFR cancelled at 1230z, OEAUT.
LOWW_APP: OEAUT, now clear of C, Squawk VFR, Frequencychange approved, good bye.
Pilot:    Squawk VFR, approved to leave, OEAUT.


  • Very often, Y flight plans are used and already contain position and altitude for the planned/wished IFR cancellation.

from VFR to IFR ("IFR-Opening" / "IFR-Pickup")

IFR pickups are used to start from an uncontrolled/info airport and to continue the flight under IFR conditions starting with a certain position. In this case, the pilot already files a Z flightplan with Delivery which therefore should also be visible to the controller. IFR pickups are often the last option for VFR flights to reach their destination despite imminent IMC conditions.

An example for a proper IFR pickup:

Pilot:    Wien Radar, OEAUT
LOWW_APP: OEAUT, Wien Radar, go ahead.
Pilot:    OEAUT, Diamond D-Jet, inbound Sollenau VOR, 2500 Feet, request IFR Clearance.
LOWW_APP: OEAUT, Squawk 4601
Pilot:    Squawk 4601, OEAUT.
LOWW_APP: OEAUT, Wien Radar, identified, 2 miles south of Sollenau VOR at 2500 Feet. Cleared Destination Budapest, direct Sollenau VOR, thereafter flightplanned route, 
          FL170, climb to FL170, IFR starts passing altitude 5000 feet.
Pilot:    OEAUT is cleared to Budapest, direct to Sollenau VOR, thereafter as filed, climbing FL170, IFR starts at 5000 feet, wilco, OEAUT.
LOWW_APP: OEAUT, Readback correct.
Pilot:    OEAUT passing now 5000 feet.
LOWW_APP: OEAUT, IFR starts now, time 1325z.
Pilot:    Roger, OEAUT.

An example for an IFR pickup because of increasingly bad visibility:

Pilot:    Wien Radar, OEAUT.
LOWW_APP: OEAUT, Wien Radar, go ahead.
Pilot:    Diamond DA-20, Altitude 5000 feet, now IMC, request IFR Pickup to Wien, OEAUT.
LOWW_APP: OEAUT, Squawk 4601.
Pilot:    Squawk 4601, OEAUT.
LOWW_APP: OEAUT, Wien Radar, identified, cleared Wien via radar vectors, altitude 5000 feet, IFR starts now, time 1450z.
Pilot:    Cleared Wien via radar vectors, altitude 5000 Feet, IFR starts now, OEAUT.
LOWW_APP: OEAUT, readback correct, turn right Heading 090.
Pilot:    Right 090, OEAUT.
  • Please note this article only lists example procedures but in no case substitutes proper preparation and the mandatory usage of the respective charts!