Background: From PCN to PCR - what's changing
The ICAO (International Civil Aviation Organisation) has agreed with Amendment 15 to Annex 14, Volume I a new system for assessing the load-bearing capacity of aerodrome surfaces: ACR-PCRshort for Aircraft Classification Rating and Pavement Classification Rating. This new system replaces the previously used ACN-PCN system (Aircraft Classification Number - Pavement Classification Number), which has been in use worldwide for decades.
The decisive difference: While the old system made highly simplified assumptions about the load from aircraft, ACR-PCR allows for a More precise and individualised assessment the actual utilisation of runways, taxiways and aprons. The aim is to More efficient use of infrastructure, Reduced maintenance effort and thus ultimately also a Reduction of emissionsfor example through less frequent construction work.
New concepts and principles
The core components of the method are
- ACR (Aircraft Classification Rating): describes the load that a certain type of aircraft exerts on a surface.
- PCR (Pavement Classification Rating): indicates which ACR values a certain area permits - i.e. which aircraft can be safely operated there.
The system takes differentiated account of various factors such as Tyre pressure, Weight, Structure type of the covering and Operating category.
Important: One Mathematical conversion between the old ACN-PCN system and the new ACR-PCR is not possible. This means that operators and pilots must familiarise themselves with the new values and adapt their planning accordingly.
Timetable for implementation in Austria
Although ICAO has postponed the official validity of the new method to 28 November 2024 the application in the EASA member statesto which Austria also belongs, postponed to a later date. The aim is to Synchronised implementation throughout the EU.
The specific date for the introduction in Austria will be determined by the Austro Control will be announced separately. Until then, the existing system will remain valid.
First published PCR values: Vienna and Graz make a start
The first airfields in Austria that have already Publish PCR values according to the new methodare:
Vienna-Schwechat Airport (LOWW)
The main runways 11/29 and 16/34 each have a PCR from 900 to 1100 depending on the construction method and taxiway section. Zones with particularly high load-bearing capacity (e.g. concrete construction) achieve the maximum PCR category R/B/W/T 1100which is sufficient even for the heaviest commercial aircraft.
Graz-Thalerhof Airport (LOWG)
Differentiated values were also recorded in Graz. The main runway 16C/34C has a PCR of 470 F/A/W/T while concreted apron areas (e.g. Apron SOUTH Concrete) with PCR 800 R/A/W/T are classified. Taxiways and asphalted aprons are significantly lower, in some cases at PCR 75-165.
Explanation of the classifiers:
- F/R: Flexible (asphalt) or rigid (concrete)
- A/B: Aircraft operation category (e.g. All aircraft, Business jets)
- W: Wet conditions considered
- T: Evaluation type (Technical evaluation)
Advantages and significance for pilots and operators
The new ACR-PCR method brings tangible benefits for all involved:
- Operator can manage their surfaces more effectively and plan maintenance cycles more economically.
- Pilots and dispatchers receive more precise information about the navigability of aerodrome areas.
- Aircraft manufacturer can document the ACR values of their models with greater accuracy.
- Regulatory authorities gain a more reliable tool for safety assessments.
In addition, the new method promotes the Climate protectionas unnecessary structural reinforcements, pavement replacements and temporary closures can be reduced.
Outlook
The introduction of the ACR-PCR method represents a important step towards modern, data-based infrastructure management in the aviation sector. Austria's airports are already well prepared. As soon as the go-ahead is given for the nationwide changeover, more airports will follow suit and publish their PCR values - a sign of innovation, safety and sustainability in aviation.
Further information:
The latest AIC communications on the ACR-PCR launch can be downloaded from the website of the Austro Control GmbH (www.austrocontrol.at) can be called up.
Source references:
AustroControl