Mike Borgelt

Some of you guys should leave Relativity to the physicists. Hypothesising non zero mass objects at the speed of light (known as c) isn't useful. Try 0.999c. This is at least theoretically possible. You might like to contemplate what light frequency you'd see. Also search for "starbow". It is quite fascinating.

Nev wrote: If it's in ground effect you will notice it passing overhead and most likely the downwash and wingtip vortices if it's low enough. Nev Back in 1990 the ARDU guys contacted me about a problem they had with the then relatively new Pilatus PC9. The manufacturer had provided them with a position error curve for the airspeed system and had provided the FAA certification people a different one so they decided to measure it themselves. This is easy with GPS but it wasn't available. It involved flying the aircraft at less than 100 feet (IIRC it was 70 feet) while tracking with a kinetheodolite and filming. In the back seat, in place of the usual altimeter was a precision digital altimeter with one foot resolution that I had built for them. A twin was on the ground under the flight path and they flew over it at speeds from 70 knots IAS up to 240 KIAS By measuring the air temperature, baro pressure and the actual geometric altitude off the films and comparing the static pressure differences the static pressure error at the various speeds could be derived and a position error curve plotted. I went to Edinburgh base to observe and help which was just as well as I took my handheld aircraft band transceiver and the RAAF didn't have enough of them. It was very interesting observing the 1 to 2 foot jump down in the reading of the ground altimeter as the aircraft flew overhead. Fun times. They tested my altimeters on the bench and found they were more accurate than the expensive bench test gear they had.

With GNSS navigation, ADSB out and in and the modern solid state AHRS systems which, if done right, do not suffer from the problems of the classic AH, cloud flying in gliders should be perfectly safe and feasible nowadays. The problem is the concrete craniums in CASA and probably the "Karens" in the GFA.

New Zealand allows cloud flying in gliders in certain areas, Bruce.

Bert Perssons was 80 back in 2015 so that makes him 85 now.

However if you can't correctly tick the boxes on the Basic is goes to a Class 2 and CASA. If a DAME is required I can't see how the $75 saved for CASA registratio of the Class 2 is that big a deal. It also removes the silly restrictions.

Sorry, the story will remain confidential to protect the innocent the guilty and the yet to be caught. There wasn't any malice in involved, just ignorance.

Nice to hear Bert Perssons is still around. I saw him last at lunch at the Watt's bridge fly in in 2015. I told him about my plan to go to NZ and buy a Bolkow Junior several of which were for sale over there, fly it around for a couple of years in NZ on trips and then bring it home to turn into a warbird - either a Biafran Baby (look it up - fascinating story of Count Carl Gustav Ericsson von Rosen - a man who put his money and life on the line for what he believed was right) or the Swedish Air Force Armed trainer version. Told Bert there was an A model Junior being restored at Watt's so we went to have a look at it. Could tell Bert was misting up a little as he reminisced about glider towing in one in Sweden, 50 or so years before. The NZ trip turned out to be interesting. Missed out by a week on the good one. The others? Well that's quite a story involving a close brush with disaster.

Um, for an actual Class 2 an actual Doctor looks at you. The paperwork is forwarded to CASA. The actual medical requirements are exactly the same. The problem with the medical non reform is that you still front to a doctor every two years. The Brits don't have this for smaller aircraft. It is a self declaration medical. The USA has an initial aeromedico look at you (probably reasonable) then an every two year on line questionaire. Canada is going that way also last I heard. We are out of line with major anglosphere countries (the bureaucrat ridden fools in New Zealand don't count). If CASA simply added the following to the maintenance regs: If the aircraft has a gross weight of less than 600 Kg the owner may, if desired, certify the annual airworthiness of the aircraft him or herself and perform any required maintenance. It is highly recommended that if there any doubts that the owner seek professional advice to resolve them. And the following for the medical: If the pilot flies an aircraft of less than 600 Kg the medical requirement for issue of a Restricted weight RPL is that a State Driver's Licence be held by the applicant with no medical restrictions. The actual weight limit can be extended if desired. This would remove the need for RAAus, GFA and the Part 149 Charlie Foxtrot.

" Basic Medical is of course e(i - sic)nvoked as a way of getting past the idiotic Class 2 medical system" Of course it is the same medical standard as the Class 2 but done by your GP. does not really help anyone at all.

I'd have thought that 30+ years of Regulatory re-write would convince everyone that CASA isn't interested in actually finishing anything, they just want the "process" to be on-going so that they can claim they are doing their jobs.

The turn rate gyro is a single axis, strapdown mechanical gyro restrained by a spring. The MEMS gyros actually use a vibrating beam to detect turn rate. Works essentially the same as a spinning turn rate gyro. Somewhat surprisingly. As long as you rotate it around the axis it is designed to detect it will detect the rotation rate. Attitude has nothing to do with it. When thinking about this stuff getting the reference frames right is essential, it is easy to mentally move from one to the other without realising what you just did. There is the Earth reference frame and the aircraft reference frame. You are effectively trying to find the relationship between the two

Bruce, the old AH instruments had an actual spinning gyro which tended to maintain its orientation in space and a tricky series of mechanical devices to do long term stabilisation to keep the axis parallel to the Earyth's gravity vector. Basically a pendulum. The gyro will otherwise drift seriously in only a few minutes. It isn't a space or inertial nav grade gyro. Works well enough as if you don't generate a lift vector of 1 g directly opposite to the Earth's gravity vector on average over minutes you aren't in an aeroplane anymore. The new gyros are what is called the "strap down" type. They use 3 orthogonal accelerometers and 3 orthogonal rate gyros. These are solid state MEMS devices (Micro Electro Mechanical Systems). The 3 accelerometers generate the long term gravity vector (actually they measure the lift vector of the aircraft, that needs to be on average 1 g opposite the gravity vector). The gyros give you roll, pitch and yaw RATES but not attitude directly. You need to integrate the rates to get attitude or rather changes in attitude. The accelerometers give you "level flight"that when you turn on and start up on the ground The chip that does this can be as small as 3 x 3 x 1 mm as you'll find in the R/C aircraft stabilisation devices. Now it isn't quite that simple because of limitations on the gyros and nasty things like "cross axis coupling" and gyro output noise. When you integrate noise you get a random walk as output. It IS NOT the same as averaging. Dynon also use the rate of change of airspeed for pitch stabilisation for the short to medium term. Think of these units as a turn, slip and ASI for limited panel but a synthesised display to look like an AH. Great devices, I've had one in the BD-4 since 2008 and it has never missed a beat. I bought the external compass add on and get real time wind vector also.

Why bother with antique GPS only receivers? Modern GNSS (Global Navigation Satellite Systems) receivers use all 4 major systems simultaneously giving access to anywhere from 35 to 65 satellites in view. You aren't going to run out of satellites. The 4 major systems are GPS (USA), Beidou (China - at least as good as GPS), Galileo (Europe) and Glonass (Russia). All are now global. ADSB is obsolete before full deployment.

Nice thread drift. From new aero engines to motorcycles. How about waiting to see what the new engines do? People are unlikely to spend the time and energy and money to build something that doesn't work as some have claimed. The Norton rotary morphed into the AE50 engine from Austro. Used in one UAV helo and Schleicher motorgliders. Very smooth but the engine needs disassembly every 5 years to replace a belt. Someone I know has one in a motorglider and after 40 running hours, despite meticulous operation and maintenance, all compression went away. New motor required . A$40,000. This isn't the answer you are looking for in an aircraft engine..

Maurie Bradney, long time instructor/manager of Waikerie Gliding Club also of MND. I lost a niece in the last year from that cause.

Designed to run on industry standard Jet fuel (Diesel (EN 590), Jet A, Jet A-1, JP-5, DEF STAN 91-86, JP-8, DEF STAN 91-91, JP-8+100, Chinese Jet Fuel No 3) Will also run and perform on all gasolines where necessary, 80,87,91,95 including 100LL along with all bio derivitives. Hydrogen gas.

You clearly didn't read the link I gave. These things claim to run on just about anything including petrol.

Via the latest issue of EAA Sport Aviation: http://www.ac-aero.com Series of interesting diesels. Rotax have had their fair share of problems and they aren't cheap. There is also not a lot wrong with Lycomings. Take a look at the basic engine and you won't find much you can leave out. Put a modern dual redundant computer controlled ignition and electronic fuel injection on it and you have a modern engine. The laws of thermodydnamics have not changed. No radiators, hoses or gearbox.

I couldn't care less whether someone has a licence or not as long as he/she is a competent pilot. Same for driving where presumably most actually have valid licences but you can't tell from the way they drive. Much of the apparatus of the almighty State is just theater. Have a think - would your personal aviation operation change much if all aviation regulation except "rules of the air" was abolished? It would certainly be cheaper.

IMO modern single pack paints (acrylic lacquer) are pretty good. Easy to touch up too as you can get some put in a couple of spray cans. Go single pack and save the weight. Weight is everything in a powered aircraft, particularly if you are stuck with stupid legislated arbitrary weight limits. My BD-4 was painted with two pack but knowing what I know now I'd go single pack. Also to save weight investigate Earth-X LiFePO4 battery instead of lead acid. There's a few kilos right there.

I guess you could ask the folks who made the series where they got the aircraft from.

"The higher the EGT the leaner the engine is running" As others just pointed out, that is wrong. The problem with carburetted Lycomings is that the mixture distribution isn't even at partial throttle settings. Above 7500 feet with the throttle wide open it is pretty good to the point where on my O-320 with two Lightspeed ignitions there is no rough running at all as you lean at and above that altitude. It just loses power but remains smooth. Reduced EGT, reduced CHT and reduced fuel flow. What's not to like? Interesting is that if you pull the throttle back just a little to descend which you have to do as the fixed pitch prop is running not far short of redline, the engine runs rough unless you richen the mixture a little.

I have a friend who flies them for Toll. They go to a lot of motor vehicle accidents. Which hospital they go to depends on the victim's condition, weather, fuel on the helo etc. I wouldn't think this was unusual.

NASA currently has a project where numerous small electric motors/props are mounted on the leading edge of the wing. X-57 Maxwell. https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-109.html Now about using a reverse pitch prop. Most small aircraft can already land in a shorter distance than they can take off in. So you land on the short strip using reverse pitch and get to dis- assemble and truck the aircraft out. The restriction to one engine one prop in RAAus shows up yet again the stupidity of breaking up private aviation into numerous small fiefdoms all with different rules, while we all fly in the same airspace over the same landscape.