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Conversation with an aircraft propeller designer, the ongoing search for MH370, LaGuardia Airport: Delta skids off the runway and the “perimeter rule” may become history, and NASA has plans for NP2000 propellers,
Anthony Falzone is the developer of the open source, public domain aircraft propeller design software named PROP_DESIGN.
We talk with Anthony about basic propeller design parameters and the mathematics involved. He tells us why propellers (which are really rotating wings) have different numbers of blades, and he explains propeller pitch, including variable pitch props.
PROP_DESIGN can be used to design aircraft propellers, but it also works for similar products such as propfans, open rotors, unducted fans, and geared turbofans. With the software, you can find the optimum geometry for any given operating condition, analyze takeoff condition, design swept blades, and much more.
Anthony is retired now, but he worked in the aerospace industry for over twelve years, holding positions at Hamilton Standard, Pratt & Whitney, McCauley Propeller Systems, and Atlantic Inertial Systems. He also did contract work for the Air Force Compressor Aero Research Lab, and designed the propeller for the General Atomics Predator B and Altair unmanned aerial vehicles.
Investigators find no unusual signs among MH370 pilots and cabin crew
On the March 8 anniversary of the disappearance of flight MH370, the Malaysian Ministry of Transport made available the MH370 Safety Investigation website, which provides links to the Interim Statement and Factual Information on the investigation of Malaysia Airlines Flight MH370.
Search for MH370 could end soon
Australian Deputy Prime Minister Warren Truss has said the country’s search for missing Malaysia Airlines flight MH370 “cannot go on forever.” The current phase of the search is scheduled to end in May.
NTSB issues 2nd report about Delta accident at LaGuardia
The Delta Air Lines Inc. plane that skidded off a runway at LaGuardia Airport last week injured 23 passengers and damaged about 940 feet of the airport’s perimeter fence.
Flights Between New York LaGuardia And The West Coast May Not Be A Fairy Tale
You can fly from New York’s JFK airport to California, and you can fly from Newark Liberty airport to California, but under the “perimeter rule,” in most cases you can’t fly from LaGuardia to a destination more than 1,500 miles away. Except on Saturday or to Denver.
The perimeter rule was established in 1984 to combat overcrowding at LaGuardia, but the Port Authority of New York and New Jersey is considering lifting the rule.
NASA selects UTC Aerospace Systems NP2000 Propellers and Electronic Propeller Control Systems for a P-3 aircraft
The NP 2000 propellers are large, 8-bladed propellers used on the Northrop Grumman E-2C Hawkeye (a tactical airborne early warning aircraft), the Grumman C-2A Greyhound (twin turboprop cargo plane used for aircraft carriers), and on C-130 Air National Guard aircraft.
NASA uses their P-3 for scientific investigations and as a technology test bed for new airborne and satellite instrumentation.
The Australia News Desk
Steve is solo this week as Grant returns from hot air balloon operations interstate. This week we present an interview with Andre Zimmerman from Pilatus Aircraft about the development of their new PC-24 business jet, recorded at the 2015 Australian International Airshow.
MH370 conspiracy theories and why we believe them – Rob Mark contributes to this video report.
Explore every yard of where planes go to die in amazing resolution: Bing unveils interactive map of biggest aircraft graveyard in the world – The map shows 2,600-acres of Arizona desert where several generations of military aircraft are stored. It lets you zoom in and look at the planes using an aerial view of the site.
Les Chevaliers du Ciel HD Promo – (Sky Fighters) with all actual footage.
New Hampshire lake is only ice runway in lower 48 states.
Mayday Machine – Talks about the NASA Ames Research Center, Intelligent Systems Division testing their Emergency Landing Planner software, and other automation issues.
Pilot Error – Trailer for the independent film.
Opening and closing music courtesy Brother Love from the Album Of The Year CD. You can find his great music at brotherloverocks.com.
I just wanted to clarify a few things I said, or didn’t say, in the podcast. Theodorsen worked for NACA which later became NASA. Also, I was trying to say, to improve quadcopter performance, you would want to use a axial flow ducted fan with a thrust vectoring nozzle attached. For some reason the words thrust vectoring nozzle never came out of my mouth, but that is what I was trying to say. My blog, located at propdesign.jimdo.com, has information about this type of quadcopter configuration. It was great being on the show. If you have any questions, let the guys at AirplaneGeeks know, and they will get in touch with me.
Anthony, thanks for sharing your knowledge with us. Your information was thought provoking. On the DOD news last week, they said the C130J propellers are not available because of a fire at the manufactures plant. Any insights into this matter.
I hadn’t heard about that. I found this article online regarding the fire; http://aviationweek.com/advanced-machines-aerospace-manufacturing/ge-dowty-assessing-fire-impact-c-130j-q400-programs. That’s sad to hear. Sorry, I don’t have any insights into this matter. Dowty was Hamilton Standard’s main competitor though. I guess Dowty was bought by GE, according to the article. Hamilton Standard was never bought by anyone but has merged and changed names a number of times, since my time there. If I recall, Hamilton Standard’s main benefit over the Dowty propeller for the C130J and similar high power applications is that their blades can be removed individually, on the aircraft. Making maintenance easier in some cases. Loosing the C130 business was a big blow to Hamilton Standard back then though. I remember employees grousing about it. But they came back with the NP2000 propeller and so forth, so not to big of a deal in the long run. Not sure if the newest C130’s are using Hamilton Standard propellers again or not.
Small piston planes having two or three bladed propellers are common. Times these propeller blades by hundreds of thousands of airplanes, and we are talking about a lot of propeller blades. You might say, these blades are keeping those planes in the air
( especially when flying over my house ). I remember many years ago, some maintenance people were using leading edge tape to prevent those props from getting chips and erosion on the leading edge. That damage could lead to blade failure. Could you update us, about why that practice has been discontinued.
I haven’t heard about leading edge tape being popular. My experience is that a nickel leading edge is the most common form of leading edge protection. It is a good idea to have blades with a nickel leading edge, especially if you have composite blades. Aluminum blades, on the other hand, do not require leading edge protection. They can be ground down for a period of time, and then replaced. I have wondered if it would be worthwhile, and/or possible to put a nickel leading edge on an aluminum propeller. To my knowledge, no one has tried that yet. It might be a good idea to try. I don’t know if corrosion would be a problem, due to dissimilar metals though. As far as I know, leading edge tape is not very durable and probably wouldn’t protect against much. Perhaps they are trying to protect against rain damage? Also, it would probably lead to extra vibration because it would be hard to apply to each blade in exactly the same way. If you did a dynamic balance after you applied the tape, you could minimize the extra vibration issue though. Nickel is good at protecting against impact. Tape, on the other hand, is not. Also, I have heard of some people using stainless steel leading edge protection. Nickel is better than stainless steel, for this application. I’m not sure why anyone chose to use stainless steel, perhaps it’s a less expensive metal? In any event, you would want a nickel leading edge. Most general aviation blades were aluminum. So they wouldn’t have come with any leading edge protection. If at all possible, it’s best to land and takeoff from debris free runways. Sucking rocks and things into the blades isn’t good on any part of your aircraft. It’s cool that you get to see planes flying on such a regular basis.
I should probably add, since it seems like you are concerned about blade failure over your house etc… The leading edge is a low stress area. The majority of the stress is at the base of the blade. Where the blade attaches to the hub. So it is more of a cost issue they are worried about. Protecting the leading edge will keep the blades in service longer and with less maintenance. I wouldn’t worry about blade failure due to leading edge wear. Usually, blade failure occurs because of errors in the engineering, manufacturing, or corrosion. Corrosion is also more on the engineers and manufacturing. So there are plenty of people that worry about all these things and try to take care of them. Of course, errors have occurred, but it is pretty rare to have a blade failure. I have read of cases where vibration has caused failures. That is supposed to be addressed in the engineering and flight test phases. So it’s not something you should have to worry about. On the really odd case I have read about mass unbalance leading to a failure. With no real idea of how the mass unbalance developed. Remember Murphy’s law; whatever can fail, will fail, and at the worst possible time. It’s been my experience that is very true. If you had leading edge wear that you didn’t address, that would lead to a mass unbalance, and potential failure. However, the pilot is supposed to walk around the plane and check it out pre-flight. So you generally don’t have people flying around with a ton of leading edge wear.