Sunday, July 1, 2007
Overloaded or Underpowered?
Ernie Stephens nailed it ("Overloaded or Underpowered?," May 2007, page 58). The moral of the story is definitely, "Overloaded."
It reminds me of the city of Los Angeles’ request for proposals years ago for an airborne command post to coordinate operations during a natural disaster. They wanted everything for capabilities. I am convinced they could have overgrossed a Boeing CH-47 or an Mil Mi-26. (I have been inside that HUGE Russian monster.)
Ernie didn’t have the space to address the maneuverable platform that L.A. developed for high-rise rescues that had to be lifted by a CH-47, with — to start with — a 1,000-ft riser. That is not a typo. They shortened it to 500 ft and it was still unworkable. That program was finally cancelled. The engineers that designed it had absolutely no concept of a helicopter’s capabilities or how people in a literal panic would react.
Canoga Park, Calif
You asked in May what Rotor & Wing’s readers consider the most significant technical developments of the last 40 years. I retired last year from Pakistan army aviation after 30 years as a rotary-wing pilot and instructor on five types of helicopters. In my view, the elimination of the "necessary evil" tail rotor through the No Tail Rotor (NOTAR) design of MD Helicopters was, for pilots and users, the most important thing. It not only does away with 20 percent of accidents. It eliminates the fastest and most critical rotating parts and the tail-rotor transmission. Also, it does away with one of the most feared emergencies, which pilots can’t even practice realistically without a costly simulator.
That is why many pilots were hoping that, in the U.S. Army’s abandoned Comanche program and its Light Utility Helicopter aircraft competition, MD’s NOTAR would be the winner.
We hope MD can recover so this safer, more economical, cost-effective and less troublesome feature can be a major part of our future.
Col. Sohail Ekram Siddiquir (retired)
Rawalpindi Cantonment, Pakistan
Your articles on power systems reminds me of New York Airways in 1952 ("Look Ahead: Powerplants — More Efficient, More Sources," May 2007, page 34).
We used the Sikorsky S-55 (or H-19) and the amount of maintenance and repairs it required made it difficult to meet flight schedules. Every hour, at least one machine was grounded for structural and skin repair, engine or clutch replacements, or pilot-reported, in-flight vibrations. All these problems emanated from the coupling of the rotor system and powerplant.
These machines were never designed for long-life use. They were single military-mission machines demanding a high maintenance man-hour to flight-hour ratio. These problems were well documented via FAA mechanical discrepancies reports.
Through the years with the S-58 and the Vertol 44B (the H-21), our record did not improve much. It was the advent of General Electric’s CT-58 coupled with improved rotor-vibration dampeners in the Boeing Vertol 107 and Sikorsky S-61 that helped us see daylight. Without the help, transport helicopters would not be performing as they are today.
Former Vice President of Technical Services
New York Airways
U.S. Air Force Lt. Col. Todd Worms was among those responding to retired U.S. Army CW4 Richard Dickson’s comments on the Air Force’s choice of Boeing’s Chinook as its next-generation combat search-and-rescue helicopter. The colonel’s letter ran in June 2007, but was abbreviated for space reasons. Here are the rest of his comments. — The Editor
Mr. Dickson also compared Army and Air Force maintenance standards. Regarding mission-capable rates, he is correct that the Air Force demands a higher rate. But he disregards the fact that the Army flies helicopters at a higher utilization rate, and that the Air Force uses a team of dedicated maintenance specialists to conduct daily maintenance operations instead of a flying crew chief. This allows the Air Force to demand and deliver a higher mission-capable rate than the Army. I have no doubt my brothers in maintenance can keep whatever aircraft is selected mission-capable to Air Force standards.
Lt. Col. Todd Worms, U.S. Air Force
HH-60 Evaluator Pilot, Operations Officer
41st Rescue Sqdn.
Moody AFB, Ga.
Whether every reader agrees with his assessment that it’s pointless to push for further FAA mandates to help make the industry safer, James T. McKenna did a great job of defending his point of view ("A New Sheriff’s Coming to Town," June 2007, page 4). Thanks for always making R&W such a compelling read.
Senior Vice President
Greteman Group – A Branding Agency
R&W’s Question of the Month
What are the biggest issues facing helicopter emergency medical operations in the coming year?
Let us know, and look for your and others’ responses in a future issue. You’ll find contact information at the bottom of the page.
Do you have comments on the rotorcraft industry or recent articles and viewpoints we’ve published? Send them to: Editor, Rotor & Wing, 4 Choke Cherry Road, Second Floor, Rockville, MD 20850, fax us at 301-354-1809 or email us at firstname.lastname@example.org. Please include a city and state or province with your name and ratings. We reserve the right to edit all submitted material.