What does reduced piste staggering mean?
Normally, a landing aircraft may only cross the runway threshold after the preceding aircraft has vacated the runway or a previously departed aircraft is at a sufficient distance.
The so-called Reduced Runway Separation permits shorter distances under certain conditions. This means, for example, that a following small aircraft may already overfly the threshold while the previously landed aircraft is still taxiing on the runway – provided that the latter has already passed a defined point and will vacate the runway without rolling back.
The procedure is internationally established and is based on the relevant ICAO rules for aerodrome control service. DFS is now defining how these requirements will be applied at its German control towers from October 2026.
Three categories determine the minimum distance
For the reduced runway separation, DFS classifies aircraft into three categories.
Category 1 comprises single-engined propeller aircraft with a maximum permissible take-off mass of up to 2,000 kilograms. This includes numerous typical general aviation aircraft.
Category 2 includes single-engine propeller aircraft between 2,000 and under 7,000 kilograms as well as twin-engine propeller aircraft under 7,000 kilograms.
All other aircraft belong to category 3. This particularly includes larger turboprops as well as commercial and business aeroplanes.
The categories determine how large the minimum distance on the piste must be.
For light aircraft, 600 metres may be sufficient
The minimum separation standards apply to a following Category 1 aircraft.
Such an aircraft may fly over the runway threshold during an approach if a previously landed Category 1 or 2 aircraft has already passed at least 600 metres beyond the threshold, is still rolling and will vacate the runway without a backtrack.
The same minimum applies when the preceding aircraft has taken off and has already flown at least 600 metres beyond the threshold.
For two consecutive departures, a Category 1 aircraft may be cleared for takeoff as soon as the preceding aircraft has become airborne and is at least 600 metres from the following aircraft.
For Category 2, 1,500 metres apply
If the following aircraft is assigned to Category 2, the prescribed minimum distance increases to 1,500 metres.
Here also, the preceding aircraft must either have passed this point after landing and be continuing towards the end of the runway, or already be airborne after takeoff.
The 1,500-metre limit also applies to any subsequent take-off.
This takes into account that larger and faster propeller aircraft require more safety clearance than light single-engine ones.
For large aircraft at least 2,400 metres
If the preceding aircraft is assigned to category 3, the minimum separation is 2,400 metres.
A following aircraft of categories 1 to 3 may only cross the threshold or receive take-off clearance once this distance has been reached.
The separation thus remains significantly more conservative as soon as larger aircraft are involved.
Wake turbulence separation remains in place
Important: The reduced runway separation does not replace the prescribed wake turbulence separation minima.
These apply in addition.
A smaller aircraft may therefore not take off earlier solely because the corresponding 600, 1,500 or 2,400-metre point has been reached. If a greater time or spatial separation is required due to the wake turbulence category, this remains decisive.
Especially for light general aviation aircraft trailing larger jets, this is an important distinction.
Only in good weather and with a suitable piste
The procedure may only be used under certain conditions.
The flight visibility must be at least five kilometres and the ceiling must not be below 1,000 feet.
The tailwind component must not exceed five knots.
Furthermore, the braking action must not be adversely affected by snow, ice, slush, water or other deposits. If a runway condition report according to the Global Reporting Format is available, the procedure may only be applied at Runway Condition Codes 5 or 6.
New or particularly noteworthy is that reduced runway separation is generally possible both by day and at night. At Bremen Airport, however, its application remains restricted to daytime.
A pilot must be able to judge the distance safely
Another requirement concerns air traffic control.
The air traffic controller must be able to reliably assess when the preceding aircraft has passed the required point. For this purpose, suitable landmarks along the runway can be used, for example.
Alternatively, the use of a ground surveillance system is possible, which provides precise position information for the aircraft.
The procedure is therefore not simply a clearance „on sight“, but is based on strictly defined intervals and local operational prerequisites.
Traffic information for the following aircraft
The pilot of the following aircraft receives traffic information concerning the preceding aircraft.
This lets the crew know that another aircraft is still on the same runway or has just taken off.
Responsibility for applying separation remains with air traffic control. However, the pilot must also continue to maintain a vigilant lookout and react accordingly if the situation develops differently than expected.
Do not take off following a preceding landing
An important limitation remains: The reduced runway separation is not applied between a departing aircraft and a previously landed aircraft.
This means that a pilot is not granted a take-off clearance solely on the basis of the described reduced separation distances as long as the previously landed aircraft is still relevantly on the runway.
The procedure relates in particular to consecutive take-offs and landings behind previously launched or landed aircraft.
Application at 14 major German airports
DFS generally permits the procedure at the international commercial airports of Berlin Brandenburg, Bremen, Dresden, Düsseldorf, Frankfurt, Hamburg, Hannover, Cologne/Bonn, Leipzig/Halle, Munich, Münster/Osnabrück, Nuremberg, Saarbrücken and Stuttgart.
However, the various categories do not apply equally to every piste.
Numerous runways are available for Category 1 traffic, including, for example, both runways at BER, the runway systems in Frankfurt, Hamburg, Hannover and Leipzig/Halle, as well as the runways in Nuremberg, Saarbrücken and Stuttgart.
Category 2 traffic is also permitted at many of these airports. Munich is additionally included in this group with both pairs of runways.
For combination with preceding category 3 traffic, the list is more restricted.
What does that mean for GA pilots?
For private pilots, the regulation is likely to be noticeable primarily at larger controlled airports.
For example, if you take off or land at an international airport in a Cessna, Piper, Cirrus or Diamond, you may experience ATC issuing a clearance even though the preceding aircraft is still visibly taxiing on the runway.
That is not automatically a pilot's error.
Provided all prerequisites are met and the required distance is achieved, this can form part of the regular procedure.
Such a situation can initially feel unfamiliar, especially for pilots who are mostly used to smaller airfields.
No need to accept an unsafe situation
However, a landing clearance never means that a pilot must continue a situation that they consider to be unsafe.
If the preceding traffic is unexpectedly slow, comes to a halt on the runway, or if any other uncertainty arises, a go-around remains possible at any time.
The same applies on departure: if there are doubts regarding obstacles, wake turbulence or an unexpectedly developing situation, the pilot should react accordingly or consult ATC.
Reduced Runway Separation is intended to improve traffic flow, not to enforce safety margins.
Why DFS uses the procedure
The main benefit lies in greater runway efficiency.
At busy airports, every additional second between two movements costs capacity. Especially with mixed traffic of commercial airliners and smaller general aviation aircraft, a rigid rule requiring a runway to always be completely clear can create unnecessarily large gaps.
The internationally planned reduced clearances make it possible to reduce these gaps under good conditions without sacrificing the required safety.
Conclusion
From 1 October 2026, updated rules on reduced runway separation will apply at German commercial airports controlled by DFS.
The crucial minimum distances are 600 metres for light Category 1 aircraft, 1,500 metres for Category 2, and 2,400 metres for preceding Category 3 traffic.
The prerequisites include at least five kilometres of visibility, a cloud base of at least 1,000 feet, a maximum of five knots of tailwind and good runway conditions. The prescribed wake turbulence separation remains fully in effect.
For GA pilots, it is particularly important to know that a landing clearance despite an aircraft still rolling on the same runway can be completely regular under these conditions. The new announcement creates a clearly defined framework for this from October.
Source references:
NFL
