|
Post by Tom Goodrick on Nov 7, 2008 21:00:00 GMT -5
Anyone who might consider an Eclipse should give serious consideration to an Avanti. It is better in all aspects I can see. It even carries two more passengers. At 400 knots it is at least as fast.
I just checked Avanti's airborne this evening and found six - the same number as the active Aero Commander 500's as a coincidence. While most were owned by the Piaggio group with VNR flight numbers, there was one with an N number, owned by a private company, Aviation Enterprises, Inc of Wilmington, DE. But the aircraft is based in the West. Just enter P180 for type to see a list of all that are flying at any moment.
N780CA flies in the region of California, Nevada and Utah. It lands frequently at Provo, UT, (KPVU) but also at John Wayne Airport (KSNA). On FlightAware you can see over two months of activity of the aircraft. It is very active, indeed. Among the interesting flight, indicating the utility of the aircraft was a flight from KLAS to KCOE, to Mexico, and from the West to the East coast. It left Provo and flew to Teterboro, NJ via Nashville and returned to John Wayne via KLBF (North Platt, NE). It is a busy airplane.
|
|
|
Post by Tom Goodrick on Nov 7, 2008 19:54:02 GMT -5
It will be just a day or two before I can post the update.
I downloaded a newer model from avsim, the file was piaggioavantip-180.zip but I had to delete it. It caused my FS to abort. It also did not give any views out the windows as I wanted. Perhaps the problem is that my system memory is full. I had that problem about a year ago and had to dump many files. There was one problem in that using the same aircraft.cfg made the aircraft float considerably above the ground. To fix that I had to cut the leg height in half. Now the leg height in the original was about right because Flaminghotsauce used to show a photo of himself and his kids in front of the aircraft. That gave a good scale for comparison. This model had the CG only 2 feet above the ground which is not possible.
The model I have had and still must use was made for FS2002. It has no interior and shows only uncluttered views out the windows. But otherwise it looks good with two professionally dressed pilots in the front seats. Unfortunately it has no props!.
|
|
|
Post by Tom Goodrick on Nov 6, 2008 22:44:23 GMT -5
You might recall DayJet, the company renting seats on Eclipse 500 Jets for flights in the southeast USA. The company ceased doing business in September because they ran out of funds. They also cited the lack of expected performance and delayed delivery schedule of the Eclipse.
This was noted in the December issue of FLYING.
Also in the issue was an article on the Piagio 180 Avanti II which has been certified for a major increase in takeoff weight - nearly 1000 lbs - with some additional power that gives it 400 knot performance at 31,000 ft in proper temperatures. The Avanti is popular acording to schedules actually flown on FlightAware and is used very much like a fanjet. I pulled out my copy of the Avanti and started updating it. It works pretty nicely though more fine tuning is needed. It will probably go back up on my web site. It is one of the most economical jets available. The pusher props behind the wing which is behind the cabin give it low sound levels.
|
|
|
Post by Tom Goodrick on Nov 6, 2008 10:57:22 GMT -5
I do not have, and cannot install, the proper software to run the video. I gather the wings came off and the pilot was able to rotate the fuselage to fly in the "knife edge" orientaion to make a survivable landing. It is not clear to me whether there was any power. Some comments seem to indicate there was propeller power.
The most likely scenario as described in some of the comments is that it is a video of an R/C model. The model would be much stiffer than a real plane and would not break up on landing. It is hard to imagine any real plane not breaking up if landed on its side with no wings at a high speed.
Some of the comments about lift and angle of attack are ludicrous. Neither lift nor angle of attack pertain soley to the wings. Any arbitrary shape has lift and angle of attack relative to the air it is moving through. Lift has no preferred orientation - up, down or sideways but is oriented within the same plane as the angle of attack by definition.
I have done some research on arbitrary bodies immersed in airstreams. Generally they rotate and tumble which gives radically different aerodynamic forces and moments. But tail fins would stabilize the fuselage and would enable a pilot trained in aerobatic flight to hold the fuselage so a side is up and there is an angle of attack maintained in the vertical plane (geometric, not airplane).
Think of lift as just one of three aerodynamic force components acting on a body in general. The orientation of these force components is defined according to the plane of the angular displacement we call angle of attack - between the relative wind and any surface that has some flatness.
This all says that, yes indeed, the fuselage side can generate lift. The problem is its lifting area is very small compared to the wing area so it must be going quite fast to generate lift on the order of the weight. Aerobatic planes seldom do this. They lose altitude and can only do the knife edge for short distances before flipping erect and gaining altitude. They do get help in holding altitude from the prop thrust. But you can't have both good lift and good upward thrust. As more upward thrust is held the fuselage stalls out and lift decays. Unlike a wing with a typical airfoil, a rounded body generating lift will not lose it abruptly in a stall.
There are many problems in dynamics, of course. With the wings gone the moments of inertia are very low about the roll axis and lower than usual about the yaw axis. Thus the aircraft could not do well in resisting prop torque. You'd get fast roll response to the torque and slower yaw response, both poorly controlled. Cutting the engine would be the only way to attain control.
|
|
|
Post by Tom Goodrick on Nov 5, 2008 20:49:49 GMT -5
After fixing the landing gear problem on the Bristol 170, I used it to fly a 12000 lb payload from Vancouver to Powell River, B C. The Bristolhas both main and aux tanks that can hold a considerable amount of fuel. But, with a 12,000 lb payload, you can nly load 325 gallons of fuel. This amount can carry you a total of about 262 nm at 75% power at 2,000 ft where you see 150 knots true airspeed. Yesterday when I found a problem with the landing gear while taxiing, I was hauling 5000 lbs of cargo. I don't remember how much payload I carried during the initial testing. You have to try a considerable range of payload to find the trouble spots in landing gear. Today I trested 0lbs, 3000 lbs, 5000 lbs and 12000 lbs. I also enhanced the lift of the flaps so you can get better bush performance. My landing with 12,000 lbs was at 67.3 KIAS and -202 fpm. If you want a copy of these improved FD files, send me an email.
|
|
|
Post by Tom Goodrick on Nov 5, 2008 20:34:52 GMT -5
The fix is usually a matter of increasing the wheel compression for the main wheels. This is the number just ahead of the value "2.5" which is the universal G for that amount of compressions. In the case of the Bristol, I changed it from 0.35 to 0.5 feet in this line:
point.2= 1.000, 3.000, 13.800, -9.100, 1600.000, 2.000, 2.000, 0.000, 0.500, 2.500, 0.850, 0.000, 0.000, 7.000, 0.000, 0.000
This seems to have fixed the problem in the many landings, taxiing and takoffs I made today. Here are some considerations. note the numbers 2.000, 0.000, 0.500, 2.500, 0.850 in the line above. The 2.000 is the radius of the wheel in feet. It merely gives you a hint of the scale but should not be considered directly related to the compression. The next value 0.000 is the mount of steering. The value 0.500 is the stroke of the gear to the 2.5 G loading. When the gear sits steady as parked, it experience 1.000 G of compression. I simplified rule in dynamics is that if you release a landing gear with a simple compressed spring that starts uncompressed and then falls very gently with gravity imediately compressing the spring until it pushes up with enough force to stop the compression, it will develop a force/weight ratio of 2.0 G's. Give it a little more as in a downward velocity at the start and you'll get close to 2.5 G's. This is universal so it should be this way in all landing gear specs in FS.
The compression of 0.5 ft is the total stroke of the landing gear at that 2.5 G force ratio. This sets the stiffness of the spring for static compression. Don't think of this as a compression of the tire itself. It is the entire compression stroke for the gear. It is vital to the physics of landing where the integral of the force over the stroke of the gear must equal the intitial downward energy of the gear. It absorbs the energy. The harder you hit (vertical rate), the more the gear will compress. On some well-made modern aircraft models for FS, you will see this compression.
The value 0.850 in the line above is the ratio of damping to critical damping. This can never be greater than 1.0 and normally lies between 0.7 and 0.95. To a large extent this behaves as in standard vibration theory. The higher the number the more the spring is damped so you won't bounce back into the air. But in a sim it plays a more significant role. The vertical rate determines the damping force in relation to this damping ratio. At the moment of first contact of the wheel, an upward force on the aircraft is generated proportional to the vertical rate and to this damping ratio. This can have a very bad effect on some landings. But it also helps eat up initial energy of impact. So it is a trade between generating too much initial force and taking the energy out of the bounce before something bad happens.
I just had an instance where the damping ratio played a big part. I was landing a T-33 jet trainer and rocked to the right just before touch-down. The force on the right main gave a big rotation to the left which almost resulted in contact of the left wing. In that case i increased the stroke slightly and decreased the damping from 0.95 to 0.85 and made the airplane easier to land though I try hard to keep the wings level during landing.
The only way to fix these problems is by trial and error with these numbers.
CG position is another big aspect of this but that is another book.
|
|
|
Post by Tom Goodrick on Nov 5, 2008 10:51:28 GMT -5
My little walk was worth it even though my vote is note reflected in the Electoral College.
Last night I tired of the election news and went to bed early. Every channel showed maps with different colors. I did manage to catch McCains concession speech ( a good one) and Obama's acceptance speech (also good). But in searching for a late TV show to put me to sleep, I found an old black and white movie from the 1930's about a test pilot who had trouble flying a Bristol 170. he managed to land it and walk away after an engine fire and a door that opened in flight (not sure how that happened but it was interesting seeing him climb around inside that airplane trying to close it. The whole movie seemed more about how being a test pilot can stress a marriage. So I woke up and came into the den and fired up FS to fly the Bristol
I had not flown the Bristol in many months since working on the FD files. I was operating in partial darkness (didn't want to awaken the sleeping bird). I failed to see that it had flaps so my first landing was a bit fast and used the whole runway at Vancouver Intl to stop. Then while taxiing back the plane became divergent in pitch (on the ground) and hopped into the air and settled on its tail, sinking straight into the ground so only the nose and props stuck out. I remember putting in a lot of hours testing that and yet this problem remains.
So my next order of business is to fix that landing gear problem. Sorry if it has caused any trouble for BGA pilots.
|
|
|
Post by Tom Goodrick on Nov 4, 2008 18:33:41 GMT -5
Today was a beautiful day to vote here in the South. I cut my tennis playing short - not doing well anyway; had a quick and reduced breakfast and then walked the five-six blocks to a church and voted. It was a beautiful day for walking, 62 degrees when I left the house just before 10 am and in the upper 60's when I returned at 10:45. The only line was at the table for E-K people where there were about 6 people ahead of me. The effort was worth it no matter what the outcome. But it looks very promising.
|
|
|
Post by Tom Goodrick on Nov 4, 2008 9:50:42 GMT -5
Yes, here's the set of lines for the default DC-3:
[LIGHTS] //Types: 1=beacon, 2=strobe, 3=navigation, 4=cockpit, 5=landing light.0 = 3, -27.20, -46.3, 0.65, fx_navredm , light.1 = 3, -27.20, 46.3, 0.65, fx_navgrem , light.2 = 3, -64.00, 0.00, 2.72, fx_navwhi , light.3 = 1, -36.80, 0.00, 6.25, fx_beaconh , light.4 = 4, -6.00, 0.00, 1.80, fx_vclight, light.5 = 4, -15.00, 0.00, 4.20, fx_vclighth, light.6 = 4, -21.00, 0.00, 4.20, fx_vclighth, light.7 = 4, -27.00, 0.00, 4.20, fx_vclighth, light.8 = 4, -33.00, 0.00, 4.20, fx_vclighth,
|
|
|
Post by Tom Goodrick on Nov 4, 2008 0:07:45 GMT -5
The Santa Fe's Desert Commuter is running fine though it had some growing pains. In working with just the east half (CACB), I had an interference after 3 hours. Not sure what happened that time. Three trains ended up connected together and running very slowly. I checked the track work and decided to put in block signals. While checking four trains running after that I found a problem that could have caused the first problem. I was switching my view beteen the four trains but on each train I had the view set off to the right side so I could see the block signals. Suddenly one signal was yellow and the train went to half speed. I switched to map mode and checked the positions of all four trains and found one where I didn't expect it. Then I noticed it was running backwards. I had been using various sets of two or three locomotives. This one was a dual F-7A set with one facing backwards. When I took manual control of the train I found it was responding backwards to the throttle. Evidently the control had switched from one cab to the second cab. The remedy was to use only F7A and F7B units. This has now worked for many hours of testing. I also put in more blocks on the loop so each block is about 1/6 to 1/8 of a loop. But I have not seen any more cases of interference.
I completed the track work for both east and west sections and extended the CFCG line. I found with these reversing loops that the passenger cars can jump the track if going over the frog faster than 18 mph so that is the manual speed now set. Autopilot with speed zones does not work because the autopilot senses an approaching turnout that is not properly set and stops.
I have completed about 60% of the scenery. While doing that I became interested in the strange traffic patterns that develop when you connect roads for cars and trucks. I built up a center section of the City (C) with tall buildings and a slightly remote suburb connected by car traffic which runs extensively around the city. At intersections I thought the cars turned randomly but they don't. If you distinguish between left and right hand "turnouts" ib the roads at intersections, the car always goes straight through left-hand turnouts and turns to the fork on right-hand turnouts. There seems to be no control. But the resuting traffic patterns are rather interesting.
When I stopped playing with the roads in "Surveyor" mode and ran trains in "Driver" mode, I found the road section with the interesting traffic in the suburban area could not be seen from any train! So I put in a freight spur track to a warehouse next to the residential area. This let me put a couple cars there and gave me a viewpoint for watching the car traffic.
So now I run 9 trains on auto and have two freight engins and several cars that I can manipulate in the yard or make runs to the warehouse as well as just sitting and watching the traffic.
|
|
|
Post by Tom Goodrick on Nov 1, 2008 16:51:42 GMT -5
I decided to take a break from flying and work on a railroad for a while. I've always been interested in trains because they made big impressions on me when I was a young child in Owatonna MN in the 1940's. My mother took me with her several times to visit her parents in Iowa. A few times we road in trains pulled by stinky and noisy steam locomotives. But most of our experience was with trains pulled by sleek and shiny diesel locomotives on the Rock Island Road. Then there were the times when our family went down to the train depot to watch the "400" come through town. It was pulled by a streamlined steam locomotive coming all the way from Chicago on its way to Seattle. So I tried various toy trains and a little model railroading. These efforts were not very rewarding because of many little details like track corrosion and never having enough space. In college I attempted to make an "N" gauge layout that would sit store under the bed and run on the bed in my rented sleeping room. The layout design was fine - a double-track mainline between two loops with the second look hiden below the table top. The only problem was I built it hurridly in the evenings of scrap wood in the engineering shop of the Aeronautical Engineering building and neglected to leave sufficient space between the bottom of the table top and the top of the lower shelf so the train could get to the lower loop. I considered myself lucky to have finished the basic build without getting into trouble so I never went back for the considerable re-build that was needed.
I used passenger trains twice in my adult life as they were fading from the scene in most parts of the US. I took a long trip from Minneapolis to Omaha to compete in the tryouts for the US Air Force Academy. That involde an layover from midnight to 6 am in the depot in Desmoines, IA. I did well on all tests and the physical competition but flunked the physical when I told the doctors about a stomach ailment that had bothered me for years in high school. They called it pre-ulcers. The trip back was extremely long.
While working as an engineer in a Boston suburb, my boss talked me into taking a management course in Boston with a staff car ride to and from the classes. That sounded great. We got the staff car ride the first day and then a general officer came to visit and he got the staff car the rest of the week. I learned how to take the train from a suburb into downtown Boston. (There was no respectable place to park a car in the city so the train seemed the best deal.) I drove 25 minutes from my home in Bellingham to Framingham and then rode the train into South Station in Boston. I sure beat driving except for one day when it snowed in the suburbs and rained in Boston. Driving through the snow was no fun and then there was the six-block walk in driving rain from the train station to the class at the Customs House. The kicker is that a month later a secretary called to say I had not been eligible for the class and the "A grade" I got in it would be striken from my record! One of the other students, who was a real jerk in the class, later became the Director of my Laboratory.
So I began to get the idea that the time for practical train transportation had passed. Today there are about 4 through-trains a day and two local freights on tracks 3/4 mile from my house. Freight trains are active links in our tranportation system. But there is no passenger service to our city (Huntsville, AL). I'd have to drive to Nashville or to Birmingham to catch a train. Each is over an hour's driving time.
But the train simulators have come along to re-kindle interest and spark fond memories. They are a lot cheaper and less trouble than model railroads. I tried the Microsoft Train Simulator and found it neat in some ways but very bothersome because of bugs. Certain turnouts and cross-overs caused mysterious derailments. locomotives could only couple on one end. Designing custom track was not easy though I put in some return loops so I could turn my yard engines. It didn't take long before I tired of the program crashes.
A couple years ago my son gave me a copy of Trainz 1.5 that he'd gotten for $1 in a deal for several pieces of software on Ebay. That seemed to work great. I ran the layouts that came with it and then began designing my own. I was having lots of fun until I ran into the glitch - probably cause by my low amount of RAM - of being limited to 12 cars in a freight train. Having 12 and hooking onto another caused a major system creash everytime. But designing a layout was easy and the operation was simple and looked very realistic. So I have continued to play with it from time to time.
My idea of a good layout is one where you can set up a few trains to run automatically while you horse around in a yard with freight or various other things. I designed one layout that worked well keeping my interest for some time. It involved two passenger trains chasing each other on a single loop which actually looked like a double-track mainline between two distant cities with an independent freight line that has a yard in each city and several industry sidings between the two cities. It had the three main features of the complex cities and the long three-rail cross-country route. To add interest I put a road in parallel with the rails between the two cities so you could also watch cars driving on the roads as the trains passed. There are hills and rivers and remote sidings for coal. Unfortunately I did not know how to set the hand brakes on cars left on sidings so there were a number of crashes as cars ran off the ends of sidings near cliffs or ran down into the industries below the hills. I'll fix that some day.
My current project has kept me very busy for a couple of weeks. It is set in the desert in the Southwest US. It is mainly a passenger train system for commuters at four out-lying towns bringing them into a central city with a train also connecting the central city to two distant cities. Its operation involves nine simultaneous trains running continuously on two loops and one end-to-end. Showing my considerable imagination I call the depots A B C D E F G. A and B lie east of the central city C and D and E lie west of it. F is a big city north of C and G is a big city south of C. Four trains chase each other on the loop that goes CACBC and four other trains chase each other on the loop that goes CDCEC. While this goes on, another passenger train goes continuously from F to C to G to C to F. The neat thing is when you see five trains simultaneously go through the main "Union" station at C.
There is also a small yard for me to play in while these nine trains are running. The yard is at C, connecting to each of the other loops. The yard includes an operating round-house for turning locomotives, diesel fuelling facilities and sorting facilities for passenger car cleaning and refurbishment. Also observation cars can be added to some trains. Each of the nine trains can come into the yard for a complete change to fresh equipment.
To add interest, I decided each of the small depots in the boondocks needed a small freight siding so they can get periodic deliveries of oil, gasoline, frozen foods and hardgoods since each community is isolated by the desert - no roads! So part of my yard work is to set up a pair of tank and box cars for delivery on the back of a passenger train to the out-lying depots.
To keep the trackwork within reason, you can go from the yard only to the CB train or to the CD train. To get the freight to A and to E the cars must ride CBCA and CDCE.
The connection from C to the outer world is the FCGCF route which is a simple single track with a small turn-back loop at F and G. This works automatically with each turnout at a fixed setting if the speed is a about 16 mph with smooth trackwork at the turnouts. This is adequate for effect.
The trains on the true loops are set on auto using speed signs that slow the train to 10 mph near each depot and 40 mph in between. Point-to-point times are about 18-28 minutes. I use manual control to drop off the freight cars. Then I run a little fast on manual to make up the time lost to the operation. With no manual operations, trains remain suitably separated for as long as I have run the system (1.5 hours so far). I could put a block in one side of each loop if needed to assure a minimum separation.
As you might expect, the desert scenery is a little sparse. But it does look interesting as you follow the motion of the train either from external chase view or from the tracking cameras. The track is laid all at zero elevation. (But, the CFG train has two trestles where it crosses other tracks.) There are gorges for rivers and dry washes. Terrain is mainly two colors, a beige for sand and a red dirt color. There are patches of dried grass and sage brush. Hills and small mountains pop up of various shapes and sizes with some red color and some light sandstone color. The hills are sufficiently numerous to keep the horizon mostly bumpy as viewed from the train.
There are suitable specimens of cactus. Water drains from washes into natural holding basins near each depot. There are some grass and trees in these areas.
I spent many weeks over the past 40 years working at Yuma Proving Grounds. During the long drives from and to Yuma, I had plenty of time to study the scenery. Once I got out of the car and walked up a rise of rock to a peak from which I could see for many miles. While standing on "my" peak, I saw a Santa Fe diesel freight go passing my little car beside the road. It looked like a model. Didn't realize I'd walked that far. (That was in 1970.)
|
|
|
Post by Tom Goodrick on Oct 24, 2008 23:23:31 GMT -5
I have been working on special sound for the AC560. I think all the Aero Commanders were a bit noisy. I'll send you a copy of the sound file. I have been tweaking it for prop sounds. You can let me know how I have done.
Enjoy the trip.
|
|
|
Post by Tom Goodrick on Oct 20, 2008 9:15:21 GMT -5
Whatever you use get the terrain display on for this type of flying. It's a big help.
|
|
|
Post by Tom Goodrick on Oct 19, 2008 19:12:18 GMT -5
I assume you were using FSX. In FSX as in FS9, you probably need to set Automixture ON for any piston aircraft with turbocharging in order to get proper performance. Such would be the case for the Mooney Bravo. It eliminates all the mioxture adjustments. You can just leave the mixture full rich.
|
|
|
Post by Tom Goodrick on Oct 18, 2008 21:31:37 GMT -5
Allen, yes, the surface of the Salton Sea is at negative 228 feet relative to mean sea level on a Standard Day. Several airports from TRM to IPL are below sea level. I used to make many flights (by commuter airline) between Yuma and LAX noting the contrast between the low elevation around the Salton Sea and the mountains around Palm Springs just a few minutes away.
Jerry I had some trouble at Bull Frog too. The elevations there are also tricky.
|
|