FAA PERSPECTIVE Airfield Pavement Roughness

1. Federal Aviation Administration FAA PERSPECTIVE Airfield Pavement Roughness Presentation to: ASTM E17 Committee Mini-SeminarName: Rodney Joel - Airport Engineering DivisionDate: Dec. 5, 2006

2. FAA Guidance - Pavement Profile NEW CONSTRUCTION AC 150/5300-13, Airport Design • Surface Gradient • Maximum grade allowance • Change in grade provisions AC 150/5370-10B, Standards for Specifying Construction of Airports • Construction Tolerances • Acceptance Criteria

3. FAA Guidance - Pavement Profile AC 150/5300-13, Airport Design Category C & D airports +1.5 percent - Max longitudinal grade (+0.8 percent in first and last quarter of runway) +1.5 percent - Max grade change Parabolic vertical curves 1,000 ft each 1 percent change 1,000 ft - Min distance between points of intersection Relaxed for category A & B airports

4. FAA Guidance - Pavement Profile Longitudinal Grade – Category C & D Airports End ¼ Runway Minimum length – 1000 ft x grade change Grade Change 0% to 0.8% Vert.CurveLength Vert.CurveLength 0% to 1.5% P.C. P.T. 0% to 1.5% Distance Between Grade Change Minimum (1000 ft) x (sum of grade change)

5. FAA Guidance - Pavement Profile Transverse Grade – Category C & D Airports Runway Width 1.0% to 1.5% 1.0 % to 1.5 %

6. FAA Guidance - Pavement Profile AC 5370-10B, Item P-401 Plant Mix Bituminous Pavements Grade – not exceed ½ inch at any point Smoothness Finished Surface < ¼ inch in 16 feet Reject if more than 15% exceed criteria Optional Profilograph

7. FAA Guidance - Pavement Profile AC 5370-10B, Item P-501 Portland Cement Concrete Pavement Grade not exceed 0.4 inch (12mm) at any point Smoothness Finished Surface < ¼ inch in 16 feet Reject if more than 15% exceed criteria Optional Profilograph

8. FAA Guidance - Pavement Profile When tolerances are within the quality limits specified,experience has shown that the current FAA grade and straightedge criteria provides pavements that are safe for aircraft operations with regards to accelerated gear load, fatigue damage, pitch & roll, and cockpit g-forces. This criteria may not address isolated exceptions such as harmonic oscillations

9. Unacceptable Excessive Acceptable Bump Height, cm ICAO Slope Change Limit(1.5% between consecutive slopes) FAA New Construction (6mm per 5 m) ICAO Tolerable Limit(30mm per 45 m) ICAO Standard of Construction (3mm per 3 m) Bump Length, meters FAA Guidance - Pavement Profile BOEING BUMP(appears to address gear load issues for a single event) Meeting the FAA design and construction criteria (0.25” per 16’) or the ICAO (3mm per 3 m) criteria produces pavements which are safe for aircraft operations

10. Pavement Roughness EVALUATION OF EXISTING PAVEMENTS There are several tools and methods to measure and evaluate a pavement profile. Parameters under consideration include: • Boeing Bump • CG or Gear Acceleration (aircraft response) • IRI • Bandpass Filters • Power Spectral Density • ETC...

11. Pavement Roughness EVALUATION OF EXISTING PAVEMENTS • There is no industry standard which clearly defines when an airport pavement has become “too rough” • Problems can be aircraft specific • New Construction criteria is not applied • Action is initiated by pilot complaints

12. Pavement Roughness – Existing Facilities

13. Pavement Roughness – What Next? FAA Tech Center – Airport Pavement Roughness Criteria “develop practical procedures for measuring and characterizing the roughness of runways and taxiways” Simulator Study Dr. Hayhoe will discuss Industry Efforts ??