In the yellow arc

DA20-C1s enter the yellow arc at 106 knots. With the MT cruise propellers they will pretty easily cruise at 120-130 knots and even slightly faster when equipped with wheel pants. With an old Sensenich wooden propeller, mine does cruise at just below the yellow arc.
 
My vintage Mooney is likewise, it will happily cruise in the yellow and will not easily descend in the green. This had been a concern, since most summer days where I live are anything but smooth. However, those with venerable Mooney wisdom have told me that this isn't as worrisome as it may seem, that Mooneys are built stout.
 
Shepherd said:
I know at least one Light Sport with a Vne of 180 kts, and can go into the yellow during a Vx climb at over 1200 ft per minute.
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May I ask which LSA is that? The Arion Lightning or other? Just curious as it indicates (to me) that the airframe is more capable but slowed to conform to LSA regulations.
 
Skyrys62 said:
I come waaaaay too close to these yellow arcs often.

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That's the golden arches. If you want the golden arcs you have to go to McDowells. There you can have the Big Mick rather than the Big Mac. They both have two all beef patties, special sauce, lettuce, cheese, pickles, and onions. McDonald's has sesame seed buns. McDowell's buns have no seeds.
 
rtk11 said:
May I ask which LSA is that? The Arion Lightning or other? Just curious as it indicates (to me) that the airframe is more capable but slowed to conform to LSA regulations.
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Well, probably needs a bigger engine which may not actually be practical even if they wanted it to go faster.
 
rtk11 said:
May I ask which LSA is that? The Arion Lightning or other? Just curious as it indicates (to me) that the airframe is more capable but slowed to conform to LSA regulations.
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The Arion LS-1 Lightning. The plane is amazing.
 
flyingron said:
That's the golden arches. If you want the golden arcs you have to go to McDowells. There you can have the Big Mick rather than the Big Mac. They both have two all beef patties, special sauce, lettuce, cheese, pickles, and onions. McDonald's has sesame seed buns. McDowell's buns have no seeds.
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I'll bet the prince could afford a plane that doesn't even have a golden arc...................... :)
 
Pascal Forget said:
DA20-C1s enter the yellow arc at 106 knots. With the MT cruise propellers they will pretty easily cruise at 120-130 knots and even slightly faster when equipped with wheel pants. With an old Sensenich wooden propeller, mine does cruise at just below the yellow arc.
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Weird, my old DA20C1 wasn't in the yellow arc at 106kts...
 

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Forgive me my new guy rusty old-pilot questions. The vast majority of my flight time is in USAF planes and I don't remember no stinkin' yellow arc. C-130 had a max speed of 326 IAS. I could never get that in flight in an old E model but I hear the Hs and Js can. I don't even remember a max speed in a T-38. It must have had one but I don't remember. The T-1 (Beech 400) had a max speed of 332 IAS or .78 mach. It could exceed that in level flight.

I assume the light airplanes I have flown did have a yellow arc, but why? Is it because the VNE is a best case scenario applicable only in smooth air? Is there some airframe stress factor that relates to the green and yellow arcs?
 
INTJ said:
Forgive me my new guy rusty old-pilot questions. The vast majority of my flight time is in USAF planes and I don't remember no stinkin' yellow arc. C-130 had a max speed of 326 IAS. I could never get that in flight in an old E model but I hear the Hs and Js can. I don't even remember a max speed in a T-38. It must have had one but I don't remember. The T-1 (Beech 400) had a max speed of 332 IAS or .78 mach. It could exceed that in level flight.

I assume the light airplanes I have flown did have a yellow arc, but why? Is it because the VNE is a best case scenario applicable only in smooth air? Is there some airframe stress factor that relates to the green and yellow arcs?
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The POH for a plane that has a yellow arc on the airspeed indicator typically says to fly in that speed range with caution, and only when you're in smooth air. I assume that it's because civilian planes are usually not as sturdy as military planes.
 
I was all up in the yellow descending into D.C. the other day. That 150 knot descent in a 182 was too nice to give up.
 
Maciej said:
Weird, my old DA20C1 wasn't in the yellow arc at 106kts...
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The way I read your picture, you were at 98 knots, and it is not in the yellow. Or was it mph? Didn't look that close.
 
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INTJ said:
I assume the light airplanes I have flown did have a yellow arc, but why? Is it because the VNE is a best case scenario applicable only in smooth air? Is there some airframe stress factor that relates to the green and yellow arcs?
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First, military aircraft aren't certified the same as civilian -- so you have an apples to apples problem to start with.

Second, a war machine is probably stressed to handle a lot more G than a typical GA weekend flyer. But I can't speak for what the C-130 is stressed to.

Short version: Yes. You can overstress a typical GA aircraft with abrupt control movement or turbulence.

Long version:

14 CFR 23.333 covers how the flight envelope is defined. Not an easy read.

Vno, which is part of what defines the yellow arc, is defined by turbulence gust factor and is a mathematical creation of an envelope between a 25 fpm gust and a 50 fpm gust, extrapolated from sea level to 20,000' MSL, as it relates to airframe structural damage.

Note: Anyone who says their airframe is more stout than their yellow arc would indicate, isn't paying attention to how Vno was determined by the manufacturer to meet certification standards. If the manufacturer built it stout enough that Vno was also Vne, there wouldn't be a yellow arc.
 
Turbine powered aircraft don't have a yellow arc. Green, right to red line.

(And, since this is POA, I'm sure there is a bizarre exception somewhere.)
 
kgruber said:
Turbine powered aircraft don't have a yellow arc. Green, right to red line.

(And, since this is POA, I'm sure there is a bizarre exception somewhere.)
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Same as helicopters. Although I'm sure there's an exception as well.
 
Mine'll do it in level flight at 65%, lean of peak, below about 6000'. I'll exceed it often in smooth air. It's harder to exceed up high since Vno is IAS and at that point it's limited by Vne long before Vno becomes an issue.
 
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