March/April 2002 Trees Rarely Make Good Runways


In the Jan/Feb 2002 California Pilot, the issue of trees penetrating the 20:1 approach surface at multiple airports cost Siskiyou County the suspension of Caltrans funding to five of its airports. It also cost Dunsmuir Mott and Blue Canyon airports the suspension of their operating permits.

Was this action harsh or justified?

Jim Michel, Aviation Safety Offficer, Caltrans, provided California Pilot with significant background on both Blue Canyon and Dunsmuir. This is not an isolated problem limited to a handful of Douglas firs, nor a problem with an impact limited to any single airport, and it could be coming your way soon…

“Caltrans Division of Aeronautics (Caltrans) had been requesting tree and brush (obstructions) to be trimmed or removed for over the past 10 years. The County of Placer had been removing brush and trees, but at a rate that never completely got the obstructions problem removed and the airport in satisfactory condition.

“On October 2,1995 Caltrans performed an airport permit compliance inspection and identified unlighted obstructions (trees and brush) that continue to penetrate the airports approach and transitional surfaces. It was determined that the trees were hazardous, especially at night. Caltrans suspended night operations until the obstructions were removed or obstruction lighted. (The extent of obstruction lighting would require an FAA evaluation.)

“The Caltrans December 1, 2001 inspection, revealed unlighted obstructions continue to penetrate the approach and transitional surfaces. Caltrans also determined the current condition of the airport and its surroundings did not meet California Code of Regulations Title 21, Airport Permitting Criteria. Because of these discrepancies, Caltrans took the following action.

“In the interest of public safety, we suspended the Blue Canyon Airport Permit, effective immediately. This suspension was in accordance with the California Public Utilities Code Section 21661.2 and would remain in effect until the discrepancies (trees) had been satisfactorily trimmed or removed and the airport meets the California Code of Regulations, Title 21 Sections 3525 through 3560, Airport Permitting Requirements.

“Currently the County of Placer is acquiring additional property to remove obstructions and is working with the USFS to remove obstructions from their property. They are planning on repairing the runway lighting system and to have the airport open this spring.”

Regarding Dunsmuir Mott, a similar scenario is reported, and a rather old one at that…

“Caltrans Division of Aeronautics (Caltrans) requested trees be trimmed or removed, on and around the airport for the past 10 years. The City had been slowly removing some of the trees. In November 1995 the City requested that the FAA conduct an obstruction evaluation and issue a determination.

“On January 11, 1996 the FAA issued their determination that the trees constituted a hazard to air navigation. In July 1997, the Caltrans California Aid to Airports Program (CAAP) project provided $252,000.00 for clearing the Runway 14 approach, specifically tree removal, and obstruction lighting. As of January 20,1999, Caltrans had not received conformation the trees, which constitute hazards, had been removed.

“In accordance with Public Utilties Code 21668.2, the airport permit was suspended until the hazards were removed. On February 1, 1999, Caltrans received a request from the City to allow one way operations during daylight hours as a temporary solution. Caltrans reviewed and concluded that to provide sufficient time for the FAA to perform any re-evaluations, and to provide the City time to implement the FAA’s recommendations, Caltrans determined that reasonable conditions and the publics interest would be served by lifting the suspension to allow restricted (day light one way) operations until September 30, 1999.

“The City was cautioned this special authorization would terminate on September 30, 1999 if the hazards were not removed. On October 12, 1999 the City Manager, Mike Powers, stated trees were being cut and negations were ongoing. Caltrans informed Mr. Powers that when a majority of the trees were cut and negotiations were completed the airport could be re-opened on a limited basis.

“Inspection of the airport on December 1, 2001, revealed trees were penetrating the approach surfaces to both ends of the runway as well as the transitional surfaces. The conditions prevented the airport from meeting the California Code of Regulations Title 21, Airport Permitting Criteria. In the interest of Public Safety Caltrans suspended the airport permit, which was effective immediately in accordance with PUC Section 21661.2.”

What Happens Next?

Clearly, airports can and have been closed not due to a concerted effort by anti-aviaiton groups, neighborhood groups or politicians. In this case, all it took was neglegence, lack of local maintenance and a state agency simply doing what it is charged with doing: ensuring safe airport operations.

Airports long overdue for a tree trimming are airports just waiting to be closed. In certain cases, airport improvement funds can be used for obstacle control. Pilot associations need to communicate directly with their airport managers and help get the funding ball rolling. Unless, of course, you prefer soft field landings with a bird’s eye view.

-David R. Aldridge