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Scale Speeds

2nckayakers

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Has anyone done the calculations to see what scale the Mavic is in relation to say a small plane like a Cessna 172? And if so have you calculated what the scale speeds are in relation?

Reason I am asking is in my youth I flew out of a small grass strip airport that closed down back in '81. Part of the runways is still there and I have been making runs in the Mavic out of both runways 16 and 34 flying the traffic patterns. I want to simulate it as close as I can (within the flight speeds capabilities of the Mavic) in relation to the scale of the Mavic as compared to a small plane that would have flown out of that airport. I have already made some practice runs to get the turns down in the box but I want to work the speeds out closer to scale.

Just curious if anyone else has ever tried it and has done the math.
 
Around 70-80 knots take off speed for a 172.

So flying your Mavic at full speed you would have to speed up your clip 2.5x.
Climb out rate for a 172 is around 190meters/min (2m/sec). For the Mavic it should be 0.8m/sec.
The banking/turning should then be 2.5x slower than you usual banking while flying your Mavic.
 
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I can handle the time compression on the video but I would never be able to match the climb rate. If I had the full runway I could probably come close but the old airport was a 2500' grass strip and when it closed in '81 they built a factory on the north end of the strip and that ate up about 1100'. Over the last 35 years the trees have been creeping in on the old runways so now you probably have 1000' left. You would never make it in a 172 now days so best I could do with the Mavic is a STOL. I have made 3 runs out of runway 16 doing a standard left pattern and visually it looks pretty close to what you would have seen at the wheels up point but you have to take a steep climb out to miss the trees and power line at the end of the runway. I have to do a short downwind leg as I have a water plant to deal with on the base leg if I were to try and follow true to the old pattern, so I just take the short downwind and cut between the water plant and the end of the old runway. Since the runway is short by 1100' and I have a fence, some mast lights and the factory itself to deal with on approach I have to do a really steep approach and land on what used to be mid field.

Once you are wheels up and clear the trees I am not too worried about airspeeds or the angle of bank or turn rates. For me, anyway, time always used to slow down when you were in a light plane and you just felt like you were floating. I still get that feeling when I clear the trees in the Mavic. I have been doing takeoff at about 34 knots in sport mode and then immediately climbing out and up to 400 agl at which point I switch back out of sport mode and bring the speed down to about 17 knots depending on the wind of course.

When I turn on the base leg I start my decent about mid way through so that once I get to the turn onto final I am at about 200 agl. I would really love to be lower but between the water plant, trees and the factory I don't want to push my luck.

Right now I have only been flying the pattern off runway 16 but once I work out the turning points for the pattern on runway 34, I am going to start flying that one. I may have an easier time in that pattern since I would only have a couple of trees and a power line to deal with on final.

I am sure that if I were to use Litchi or some other mission planner I could get everything a whole lot closer, but it has been way more fun doing it by dead reckoning and doing all the stick and rudder work myself. It's what makes flying fun!

I know I won't ever be able to fly the pattern and get it exactly what it was back in the day, but I want to get it as close as I can just for nostalgic reasons. Some of the old pilots that used to fly out of there and got me started in flying (now in their 80's and 90's) still get together once a week to reminisce and I would love to be able to let them fly out of there again if only through the eyes of the Mavic.

You will have to overlook the video as I haven't done any real editing or corrections but here is the second run I made. Right now I am not trying to focus on the video and jerky motion as much as I am still trying to just get the feel and timing down for all the turns in the pattern. I am not quite there yet but getting close. Once I am happy with the pattern then I will work out all the video settings and do some better editing. Biggest thing on that is I really need to do it at high noon, or twilight. Don't want the old guys that might watch it to worry about Zeros coming out of the sun!

 
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I would love to be able to let them fly out of there again if only through the eyes of the Mavic.
That's a really nice thought. I was thinking about setting something up like that for terminal patients, or old people, to have them virtually flying over a place they would like to see before they pass away. Things like streaming and goggles make that possible. I wished I could have done that for my mother but the tech wasn't there then.
 
I don't understand how "scale" speed applies here. Since your visual reference is still the same as if you are in a real airplane, aren't actual speeds and climb/descent rates what you are shooting for?
 
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