Airspeed Bug

[soarhead]

Does anyone know how to change the limits of the airspeed bug? I can't select anything below 72 kts. I don't see anything in either the install manual or pilot guide and nothing obvious in the setup menus. The only thing I haven't tried is checking to see if the lower limit of the bug is associated with best glide speed.

 

[HFMan]

I know that if you have autopilot, you can't set the airspeed bug any lower than your minimum pitch airspeed in the autopilot setup.

 

[soarhead]

Yeah, I’m trying to bug Vapp without the autopilot.

 

[soarhead]

Actually, 1.3 VS1 is exactly what I am trying to achieve but not with the autopilot, just the bug. My VS1 is set as 48 kts yet the bug cannot be set below 72.

i’ll take a look at your reference and try that to see if does anything. Thanks!

 

[soarhead]

Lol….yeah I think that’s a coincidence. I am set up in knots.
I will check into what you both have mentioned regarding the autopilot. It makes sense actually. Could be a safe guard to mitigate someone in IAS mode having the bug set below VS1. Will be a couple of days until I get back to the airplane.

 

[soarhead]

I think you are on to it. Just doing the math now, my VS1 should be 55 Kts and X 1.3 = 71.5, the bug is limited to 72 kts. When I get back to the hangar I'll check it out and try putting in a different VS1 value to see if that changes the minimum bug setting. I'll report back but I am now 99% sure that is what's happening and I can see why Dynon would engineer it that way. Coming from an airline background, I hate having instrument bugs that cannot be put where I want them. In this case, Vapp for landing with flap 30. The question now is, do I put an arbitrary value in the Autopilot Pitch setup to allow the use of the bug below it's current value, or just put up with it.

 

[skysailor]

The way I did it was to re-purpose one of the provided bugs. You are given a place to input Vx (max angle climb), Vy (max rate climb) and Va (maneuvering speed) which show up as individual marks on the airspeed tape X, Y and A. While I always reference angle of attack (old habits which kept me alive coming aboard the carrier) I set the "A" bug at my 1.3 Vso for max gross weight as a backup. This now becomes "Approach" speed to me. It is a pilot only reference. The flight director and autopilot ignore it completely (just like Vx,Vy and Va). Perhaps you could consider this as a solution.

 

[soarhead]

So I managed to get to the airplane today and sure enough, in the autopilot pitch setup, was a minimum speed setting. I reduced this to my desired Vapp with flap 20 or 30, which was only a couple knots below what was there and bingo, I can now dial the bug back to what I want to see on approach. Thanks guys.