RVDan
I love flying!
Can Skyview do low airspeed awareness as described in AC23.1311c ?
Low airspeed awareness
- Thread starter RVDan
- Start date
Big doc there - which particular section are you referring too? I didn't find anything that matched your text with a quick search.
But generically, you care more about high AOA than you do low airspeed. Knowing when your wing is approaching its critical stall angle is really what you're after - a low airspeed indication is just a proxy for that (and only works in some situations)
RVDan
I love flying!
It is in section 17.7(a)and(b). Which also explains why it is required in certified systems.
The real trick is that it cannot show during takeoff.
The real trick is that it cannot show during takeoff.
- Joined
- Mar 23, 2005
- Messages
- 13,226
Technically, that is an AC, not a TSO, so it isn't *required* in certified systems, but it is a good idea. I bet I can find you more than one certified glass display that doesn't do this 
10 internet points if you can come up with an algorithm that will not show at takeoff but will show in the recovery from a hammerhead. This would be so much easier if we all had switches on our landing gear!
We appreciate you pointing it out. It is on our list to consider in the future. We do always try and be as industry standard as possible.
10 internet points if you can come up with an algorithm that will not show at takeoff but will show in the recovery from a hammerhead. This would be so much easier if we all had switches on our landing gear!
We appreciate you pointing it out. It is on our list to consider in the future. We do always try and be as industry standard as possible.
RVDan
I love flying!
I do STC projects for EFIS upgrades for the past 20 years and the FAA looks for this. Seems that some have missed it in the past however.
How about this for an algorithm: In the absence of a gear squat switch, do not display at power on until airspeed > Vso. It would mean that everyone would have to set Vso though.
If power was cycled in flight, the condition would immediately be satisfied and the band would be displayed.
In the hammerhead, it would still display since airspeed had to exceed Vso to get airborne and that would be correct.
Let me know if I get the 10 points...
How about this for an algorithm: In the absence of a gear squat switch, do not display at power on until airspeed > Vso. It would mean that everyone would have to set Vso though.
If power was cycled in flight, the condition would immediately be satisfied and the band would be displayed.
In the hammerhead, it would still display since airspeed had to exceed Vso to get airborne and that would be correct.
Let me know if I get the 10 points...
- Joined
- Mar 23, 2005
- Messages
- 13,226
I assume they want it not to appear on your second take-off if you do a land, taxi-back, and take-off. So just using airspeed above Vso once this power cycle doesn't seem to meet that. It needs a reset algorithm. Resetting on 0 airspeed breaks the hammerhead requirement...
3 internet points
I'm guessing they don't actually care that much about it not showing at take-off, since the most popular certified glass cockpit out there doesn't do this, it just shows red all the time.
3 internet points
I'm guessing they don't actually care that much about it not showing at take-off, since the most popular certified glass cockpit out there doesn't do this, it just shows red all the time.