Xavion

[ChristianGodin]

If any owner of 201 has been playing with Xavion, could you tell me what was your gliding ration clean and full flaps or tell me were to find that information? Thank you.

[ChristianGodin]

I was actually trying to figure out your 110. I use 87 knots.

[ChristianGodin]

Here our my numbers, but I will use your glide ratios. Are you using ilevel?

[ChristianGodin]

Jim,

Can you tell me the meaning of the bottom part of the screen attached. It's like ladder!!

[ChristianGodin]

I have a dynon d1 as a back up for attitude. So I was wandering if ilevel would make xavion more accurate in a engine falure situation?

What do you think?

[ChristianGodin]

Cool stuf coming on. Looking forward...

[scottfromiowa]

Why would you want a glide ratio with full flaps? I get best glide speed to be trimmed in an emergency, but not w/ flaps....

Garmin pilot has ADS-B now. Really nice ap with charts. Reasonable buy in price.

[romair]

Where did you get the Vfe first notch speed? I see that its different for both of you guys, and I cannot find it in my POH...

 

Stefan

89 M20J

[romair]

Jim,

Tomorrow I will try to go test my glide ratios. Under what menu will I be able to see that in?

Thanks

Stefan

[bnicolette]

Off of the Xavion website:

First, enter the best glide speed of the aircraft, as indicated in the book or you find yourself.

Then, below that, you enter THREE glide ratios:

The top is the best glide you can muster (best glide speed, all clean, proper feathered if you can).

The second is the best glide you can muster without touching the prop (best glide speed, all clean, proper set to cruise).

The bottom is the WORST glide you can muster! (flaps full down, nose pushed over to hold max flap extension speed!!!)

The way that you will FIND these glide ratios is fairly simple: FLY THEM!

Go up to a very high altitude on a day with little wind and fly the 3 configurations above, noting the “CURRENT GLIDE RATIO” displayed for you at the bottom of the screen. (The iPad knows your glide ratio by looking at the GPS to see the distance covered for each foot of descent! After all, that is just exactly what glide ratio IS!) If there is any wind at all up there, then do your glides in 2 or maybe 4 directions and average the results.

Once you have flown the 3 glide configurations above at the speeds listed in the buttons, averaged across perhaps 2 or 4 directions to correct for wind, Xavion will have a decent idea of how well your airplane glides. Now, in flight, if the engine ever quits, Xavion will set up hoops that follow a glide ratio halfway between best glide (prop cruise) and worst glide (prop cruise), so you should expect to come down with the flaps at about 50% to be right between those glide ratios, giving you maximum opportunity in flight to raise or lower flaps to stay right on the nominal glide. (Where, for us, “nominal glide” is exactly halfway between best glide and worst glide, so chosen because it allows the maximum margin for error if things go better or worse than planned due to winds or thermals).

Once you have entered this data, you should pull power and follow the hoops in the main PFD screen a few times to make sure that you like the descent rate that you have entered. If everything is perfect, you should come down perfectly down the center of the hoops at 50% flaps. If you find that the hoops are too hallow or too steep, increase or decrease the glide ratio accordingly in the GLIDE window.

Sent from my iPad using Tapatalk HD

[bnicolette]

I haven't gotten around to doing it yet Jim but will try to get it done this week. I will post results when I get them done.

Sent from my iPad using Tapatalk HD

[Earl]

I just bought a new iPad and installed Xavion.  Haven't added the numbers yet but hope to get out and test my book numbers from the POH.  Any 252 drivers out there that have used this and can share their numbers?

[ChristianGodin]

I fly a 201 and I tested Xavion. It is surprisingly precise...

[romair]

I finally got around to flying the glide ratios yesterday. For each of the glide ratios I flew N, E,S, W, then averaged it. This is what I came up with in my 1989 M20J:

Throttle out, propeller at the lowest RPM possible (know pulled all the way back), maintaining right around 90 kts for glide speed - glide ratio 14.5

Throttle out, propeller in cruise (around 2400 RPMs before throttle was pulled out), 90 kts: glide ratio 11.8

Worst glide speed (flaps all the way down, gear up, prop around 2400 before pulling throttle out), maintaining around 105 airspeed: glide ratio 7.5

 

Quick question for anybody who actually tried it out to see if it get you to the runway. Is there a way to tell Xavion which end of the runway you want to use? I wanted to try it last night, I was coming to my airport from the South, and the wind was from 160, so I wanted to land on 17. But Xavion of course found the glide ratio for the airport, but was having me land on 35. There were other airplanes in the traffic pattern, so I did not try it out. I couldn't find anything that I could press in order to make Xavion change the runway end.

Thanks

Stefan

'89 J

[Marauder]

Stefan -- I think I remembered seeing it in one of Austin's videos or reading it somehwere that the software uses wind calculation to determine which runway. If there is no wind (i.e. you have no ADS-B information) it defaults to the closest runway approach.

 

Jim, Christian or Brett would know for sure. I'm still trying to get to stop saying "attitude, attitude"

 

Thanks for providing the numbers. I will do my testing when I get my plane back tomorrow.