VicariousLiving
New Member
Texasspilot said:
Now there's an obvious oxymoron. You might wish to review the definition of "critical engine".
Counter-rotating props essay
- Thread starter riot shields
- Start date
Now there's an obvious oxymoron. You might wish to review the definition of "critical engine".
Airdale
Well-Known Member
A little late to be doing a report huh?
All you need to know are basic aerodynamics. P-Factor, Accelerated slipstream, Spiraling slipstream and Torque. These apply to every propeller driven airplane, including twins. The problem with a conventional twin (both props rotating clockwise when viewed from the cockpit) is, one of those engines will produce more adverse handling effects than the other, based on the propeller rotation in relation to the aircraft's CG. Make one engine rotate in the opposite direction, you eliminate the "critical engine". On a conventional twin, the critical engine is the left. Understand those aerodynamic factors I stated above, and you'll understand why the left is critical.
Counter rotating propellers, eliminate the critical engine, which basically means that either engine, when failed, will produce similar aerodynamic tendancies to the other.
All you need to know are basic aerodynamics. P-Factor, Accelerated slipstream, Spiraling slipstream and Torque. These apply to every propeller driven airplane, including twins. The problem with a conventional twin (both props rotating clockwise when viewed from the cockpit) is, one of those engines will produce more adverse handling effects than the other, based on the propeller rotation in relation to the aircraft's CG. Make one engine rotate in the opposite direction, you eliminate the "critical engine". On a conventional twin, the critical engine is the left. Understand those aerodynamic factors I stated above, and you'll understand why the left is critical.
Counter rotating propellers, eliminate the critical engine, which basically means that either engine, when failed, will produce similar aerodynamic tendancies to the other.
Wannabe2
New Member
University of North Dakota has a website where I found all kinds of good info on single engine ops, vmc stuff etc. Some really great interactive stuff where you can change different factors and see what is happening to the aircraft. I can't seem to find the link on thier website to it though. Perhaps there is a UND student/grad that knows how to get there.
I have been instructing in the seminole for a year or so now and if you have specific Q's I would be glad to answer anything that I can...
I have been instructing in the seminole for a year or so now and if you have specific Q's I would be glad to answer anything that I can...
Wannabe2
New Member
Here's the link, I finally found it. As of a couple weeks ago now you need to get a login from them, but it is well worth the time to get one. Great stuff there.
http://media.avit.und.edu/login.php
http://media.avit.und.edu/login.php
greaper007
Well-Known Member
I have 200 hours in a Duchess but zero in any other ME airplane. So my question is, is the Seminole as much of a dog as the duchess? We get a decent climb rate but very rarely see airspeed over 115 or so in cruise.
Stone Cold
Well-Known Member
Yeouch, that sucks...Blue line in both my airplanes is ~104...that's a very low cruise for a twin.I don't remember how bad the cruise was in the Seminole, but I thought is was definitely higher than that (115). Of course, you are just trying to build time right now, right? So, what's the rush. I get paid to rush as much as safety and practicality allow. I am also still building time, so I'm not sure how much rushing I should be doing.