Joined: 01/09/09 Posts: 1198 Location: Burlington, ON CZBA
Aircraft: Looking for an A36
Username Protected wrote:
im no injuneer either. but if you do the turbine conversion to an A46, it eliminates the yellow arc all together, Vne does NOT change though. all that means is that the A36 is much stronger than beech wants you to think. I believe the yellow arc is for full power descents in baby butt smooth air... btw, i hit 249 GS the other day on the way down. I didnt ask atc for a GS check..... dying to break the 250 barrior
I am perfectly willing to be educated here...but I was seriously considering one of the Tradewind turbine conversions and I was lead to believe that the yellow arc was indeed eliminated because VNE was at the START of the old yellow. And there was a very annoying, not turn-offable buzzer to enforce that.
I never got around to flying one, but I believe that the above is correct.
Jim
Jim, I'm also willing to be educated, and probably will be
Turboprops don't have yellow arcs. It's green then VNE. In the turbine bonanza VNE is where the yellow would start, meaning VNE is where green ends.
My concern is that the plane was designed to operate in that realm with all parts were new. Once it gets to be 50 years old, I assume that it's no longer at 100% of its original strength.
Also, depending on rate of descent, around the Great Lakes you can get layers of wind shear and hit some fairly good bumps without warning.
The way I look at it, if there was enough evidence that the strength of the aircraft is sufficiently diminished by age that the yellow arc is no longer valid for smooth air, there would be an AD before you can say the second "A" in FAA.
My personal Vne is only 14 knots above the green arc, just in case there is any shear.
_________________ Marc Zorn 1962 P35 Bonanza ▬▬▬▬▬▬▬▬▬ ▬▬▬▬▬▬▬▬▬
Joined: 08/12/08 Posts: 1536 Location: Santa Barbara, CA
Aircraft: '76 A36 Bonanza
Username Protected wrote:
I used to descend at indicated speeds in the bottom of the yellow arc in smooth air.
After reading posts from pilots I respect I now limit my indicated airspeed to the top of the green arc.
Are those different?
Yes.
Now I avoid the yellow arc always.
As others have noted in the yellow arc on a Bonanza would be past red line if you simply put in a turbine engine. Your margin of structural safety is diminished.
As others have noted you may be in smooth air and suddenly encounter unexpected turburlence. My green arc speed is well above my turbulent air penetration speed.
Plus my aircraft is flown significantly under gross weight on 99% of my flights.
My A36 is plenty quick already - I see 165 KTAS on 13 gph at altitude - if I ran it at 75% power LOP I would be cruising in the yellow arc.
I do hope to add the TAT TN eventually but I'll go higher to go faster. It's just $$$$.
Joined: 08/15/08 Posts: 472 Location: Santa Rosa, CA
Aircraft: A36
Username Protected wrote:
Surely everybody has seen this by now. This was a NASA test of some sort with a twin comanche.
Good grief, no I had not seen that before. It sure looked like failure was imminent, I can't believe they let it get that far without stopping the test. Did the tail stay on the plane?
VNE, never exceed speed, in general aviation pistons is indicated airspeed. The airplane could care less what the true airspeed is, it's indicated that counts. VNE is 90% of design speed. In a proper flight test regime flutter testing is done up to design speed and no faster. If flutter is encountered before design speed, it's back to the drawing board time. So, you can see that there is already a designed in buffer between design speed and VNE. The real important issue is control surface balance. While the Bonanza and every other aircraft that is certified in the US has been subject to flutter testing at the design point, only random conformity tests are done at the factory. Repainting, or repairs to a control surface may mean that the control no longer conforms to the certified design. Thus, it is vitally important that all control surfaces be properly balanced after any repair or repaint.
VNE, never exceed speed, in general aviation pistons is indicated airspeed. The airplane could care less what the true airspeed is, it's indicated that counts.
Actually the airplane does "care" what the TAS is, especially WRT flutter because it's the speed of the air molecules flying by that determines the potential for flutter, not the quantity. Vne is established at 75% of the airplane's service ceiling on a NA piston powered airplane with the expectation that when higher than that, there's not enough power to reach the flutter inducing TAS, even in a normal descent.
that video makes me want to install a review mirror in my plane.
Not exactly sure why the disagreement on IAS or TAS as I think Vne on IAS has a relative value to the TAS that would induce flutter leading to failure.
No need to constantly re-calculate TAS to determine if you are reaching Vne as its much easer to just look at the IAS guage and take corrective action.
_________________ Minister of Ice Family Motto: If you aren't scared, you're not having fun!
Joined: 01/07/08 Posts: 929 Location: Pittstown, NJ, Vero Beach FL
Company: Lauderdale Millwork Inc.
Aircraft: TH914 BE58 4545M
Username Protected wrote:
that video makes me want to install a review mirror in my plane.
Not exactly sure why the disagreement on IAS or TAS as I think Vne on IAS has a relative value to the TAS that would induce flutter leading to failure.
No need to constantly re-calculate TAS to determine if you are reaching Vne as its much easer to just look at the IAS guage and take corrective action.
Rick, that sounds logical at first glance but at higher altitudes it isn't that simple. But don't ask me to explain it either! Read that article written by the RV people.
Your mirror would be somewhat useless. You all do realize that the video shows the event in slow motion, right? The actual frequencies are too fast to actually visually see the deflection modes.
JS
BTW, I found it humorous that the 380 crew chose to wear helmets and chutes but no 02 masks. A far more probable required piece of equipment.
BTW, I found it humorous that the 380 crew chose to wear helmets and chutes but no 02 masks. A far more probable required piece of equipment.
I think that was required by regulation--I recall one of the pilots saying they wear that stuff because they have to, but if something really did go wrong, it was highly unlikely they could ever get out.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot post attachments in this forum
BeechTalk™ is the quintessential Beechcraft Owners & Pilots Group providing a
forum for the discussion of technical, practical, and entertaining issues relating to all Beech aircraft. These include
the Bonanza (both V-tail and straight-tail models), Baron, Debonair, Duke, Twin Bonanza, King Air, Sierra, Skipper, Sport, Sundowner,
Musketeer, Travel Air, Starship, Queen Air, BeechJet, and Premier lines of airplanes, turboprops, and turbojets.
BeechTalk.com is not affiliated or endorsed by Hawker Beechcraft Corporation, Raytheon, or its subsidiaries.
Beechcraft™, King Air™, and Travel Air™ are the registered trademarks of Hawker Beechcraft Corporation.
dying to break the 250 barrior
