Dauntless Aviation
 
FAA Written Test Prep
Checkride Oral Exam Prep
Pilot eLogbook System
Aircraft Systems Reviews
EASA Theory Exam Prep
China ATPL Theory Prep
UK PPL/IMC Theory Prep
Transport Canada Theory Exam Prep
Aircraft Recognition Tutor
SimPlates IFR Plates
FAR/AIM Reference
All Software and Apps
Aviation Freebies
Free Aircraft Checklists
MetalWings Diecast
 
Products by Platform
 
Support
Knowledgebase / FAQ
Contact
Employment
SBD Dauntless
 
Bulk Purchases
Site/Lab Licensing
Affiliate Program
 
Home

Aviation Glossary :: Obstacle Free Zone  Aviation Glossary :: Obstacle Free Zone FAA Written Test Preparation
Aviation Glossary Welcome to the Dauntless Aviation Glossary!

At Dauntless, our editorial staff maintains the web's largest unified glossary of aviation terms. This glossary is built from a combination of official, quasi-official, and proprietary sources (including original material that we develop oursselves). Uniquely, we often provide multiple definitions of a given term so that you can find that which best applies to you. In order to maximize your learning efficiency, this glossary (and similar ones for our international users) is incresingly fully integrated into our aviation learning apps, including our FAA written test prep and FAA practical test prep software and apps. If you like this glossary, you'll love them with their polished learning environments and world's best and clearest content (please do give them a try.).

Obstacle Free Zone
Obstacle Free Zone
The OFZ is a three dimensional volume of airspace which protects for the transition of aircraft to and from the runway. The OFZ clearing standard precludes taxiing and parked airplanes and object penetrations, except for frangible NAVAID locations that are fixed by function. Additionally, vehicles, equipment, and personnel may be authorized by air traffic control to enter the area using the provisions of FAAO JO 7110.65, Para 3-1-5, VEHICLES/EQUIPMENT/PERSONNEL ON RUNWAYS. The runway OFZ and when applicable, the inner-approach OFZ, and the inner-transitional OFZ, comprise the OFZ.
  1. Runway OFZ. The runway OFZ is a defined volume of airspace centered above the runway. The runway OFZ is the airspace above a surface whose elevation at any point is the same as the elevation of the nearest point on the runway centerline. The runway OFZ extends 200 feet beyond each end of the runway. The width is as follows:
  2. For runways serving large airplanes, the greater of:
    1. 400 feet, or
    2. 180 feet, plus the wingspan of the most demanding airplane, plus 20 feet per 1,000 feet of airport elevation.
  3. For runways serving only small airplanes:
    1. 300 feet for precision instrument runways.
    2. 250 feet for other runways serving small airplanes with approach speeds of 50 knots, or more.
    3. 120 feet for other runways serving small airplanes with approach speeds of less than 50 knots.
  4. Inner-approach OFZ. The inner-approach OFZ is a defined volume of airspace centered on the approach area. The inner-approach OFZ applies only to runways with an approach lighting system. The inner-approach OFZ begins 200 feet from the runway threshold at the same elevation as the runway threshold and extends 200 feet beyond the last light unit in the approach lighting system. The width of the inner-approach OFZ is the same as the runway OFZ and rises at a slope of 50 (horizontal) to 1 (vertical) from the beginning.
  5. Inner-transitional OFZ. The inner transitional surface OFZ is a defined volume of airspace along the sides of the runway and inner-approach OFZ and applies only to precision instrument runways. The inner-transitional surface OFZ slopes 3 (horizontal) to 1 (vertical) out from the edges of the runway OFZ and inner-approach OFZ to a height of 150 feet above the established airport elevation.
(Refer to AC 150/5300-13, Chapter 3.) (Refer to FAAO JO 7110.65, Para 3-1-5, VEHICLES/EQUIPMENT/PERSONNEL ON RUNWAYS.)
source: FAA Pilot/Controller Glossary

Ace Any FAA Written Test!
Actual FAA Questions / Free Lifetime Updates
The best explanations in the business
Fast, efficient study.
Pass Your Checkride With Confidence!
FAA Practical Test prep that reflects actual checkrides.
Any checkride: Airplane, Helicopter, Glider, etc.
Written and maintained by actual pilot examiners and master CFIs.
The World's Most Trusted eLogbook
Be Organized, Current, Professional, and Safe.
Highly customizable - for student pilots through pros.
Free Transition Service for users of other eLogs.
Our sincere thanks to pilots such as yourself who support AskACFI while helping themselves by using the awesome PC, Mac, iPhone/iPad, and Android aviation apps of our sponsors.

Disclaimer: While this glossary in most cases is likely to be highly accurate and useful, sometimes, for any number of editorial, transcription, technical, and other reasons, it might not be. Additionally, as somtimes you may have found yourself brought to this page through an automated term matching system, you may find definitions here that do not match the cotext or application in which you saw the original term. Please use your good judgement when using this resource.


© 2024 Dauntless Aviation • 4950C York Road 110, Buckingham, PA, 18912, USA • Contact UsPrivacy Policy