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Feb
23
2015
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Posted 9 years 65 days ago ago by Randy Rowles
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Within the FAA’s practical test standard (PTS) for helicopters, the proficiency requirements to successfully demonstrate a running/roll-on landing are identified. They are seemingly simple: establish and maintain: a shallow approach angle, a proper rate of closure, and proper flight control technique after surface contact. The PTS wants us to talk about surface texture, height/velocity diagram, and factors affecting performance data, all really good topics. However, I’ve found a question that few applicants can answer: Why are we here?
Instructors are teaching the fundamental flying skills to successfully conduct a running/roll-on landing, but very little emphasis is placed on why the maneuver may be required. The assumption by the student is that all running/roll-on landings are the same. This couldn’t be farther from the truth. The appropriate use of this maneuver must coincide with the correct scenario, or the pilot may be placing undue risk on the flight.
During the ground portion of the practical exam, many applicants will correlate this maneuver to high-altitude scenarios only. Since oral questioning presents any evaluator challenges at the correlative level of learning, I accept stated limited-scope answers, but also utilize a scenario during the flight to verify the applicant‘s complete insight into this maneuver. It is important that a thorough pre-flight briefing identifying all aspects of the flight includes how emergency procedures will be introduced.
The most common scenario requiring this type of landing is a limited power situation. Often I will introduce a low rotor RPM condition that requires the applicant to conduct a low rotor RPM recovery technique. As an example, the R22 usually cruises around 21-inch manifold pressure (MAP) for a 75kt flight profile. During the low rotor RPM recovery, the applicant will: reduce collective, add throttle, and attempt to reestablish the power setting previously held. To their surprise, I will limit them to no more than 19-inch MAP. Then I pose this question: if the governor is on and you’re not HOT (air density), HEAVY (weight), or HIGH (altitude), what other situation may cause a low rotor RPM condition to occur? The correct answer: partial power (cylinder loss, magneto, etc.). Roughly half of the applicants presented with this scenario do not know the answer.
So now that you know why you’re going to do the running/roll-on landing, what speed and landing distance should be expected? As with any landing where the power of the helicopter may be limited, a speed utilizing Effective Translational Lift (ETL) is prudent and appropriate. But what about a situation requiring this type of landing where there is no power limitation, such as a hydraulic failure. Whereas the landing with a power limitation may benefit from ETL, the same maneuver during a hydraulic failure is purely for aircraft stability, so speeds above ETL may not be appropriate. Many early turbine pilots only see this maneuver during hydraulic failure training.
The important part of teaching the running/roll-on landing is making sure the student knows which version of this maneuver is appropriate for varying situations. For example, a long, high-speed slide in a helicopter with limited controllability may prove challenging. Conversely, losing ETL 10 feet off the ground when the engine has nothing more to contribute … may prove deadly!
About Randy: Randy Rowles has been a FAA pilot examiner for 20 years for all helicopter certificates and ratings. He holds a FAA Gold Seal Flight Instructor Certificate, NAFI Master Flight Instructor designation, and was the 2013 recipient of the HAI Flight Instructor of the Year Award. Randy is currently Director of Training at Epic Helicopters in Ft. Worth, Texas. -