Can an RV level be used as a Slip Indicator?

PAgyropilot

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Just curious: Those curved levels that are used to indicate if your RV is level look very similar to a Slip Indicator.
Can an RV level be used as a Slip Indicator?

Sorry if it's a stupid question.....

Baron
 

XXavier

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Just curious: Those curved levels that are used to indicate if your RV is level look very similar to a Slip Indicator.
Can an RV level be used as a Slip Indicator?

Sorry if it's a stupid question.....

Baron
Any level indicator –bubble or ball– can work as a slip indicator. The ball/bubble is constrained is to move along an arc in a plane. Let's imagine the center of that arc as the point where the vector sum of the gravitational and inertial forces is applied. Now, you project that resultant vector on the plane of that arc. The intersection of the arc and the projected vector is exactly where the ball/bubble lies, at any time or circumstance...
 

BEN S

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shoot I remember way back when I learned how to fly from watching "Tales of the Gold Monkey" and he used a hookers lipstick and a half bottle of rum as an artificial horizon for flight in to IMC!

Seeing as how you really only need an airspeed indicator (hall works fine) and EGTs for two strokes sure, why not add a slip indicator, its one more gauge you will never look at....

Just my opinion....it was free.
 

Rattler 1

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I thought about an RV level also but decided not to use it as they are not liquid filled to dampen the movement of the ball. At least the ones I looked at. Not sure if the ball would just bounce around.
 

WaspAir

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The cheapest alternative is eight inches of red yarn.

Yaw strings are more sensitive than inclinometers, fluid damped or not. In my Bell, depending upon loading, the string and the ball don't always agree; I fly by the string in those cases, because you can be in coordinated flight with one skid low.
 

Vance

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I prefer a yaw string to an inclinometer because I feel it gives more useful information.

I won’t fly a gyroplane without a yaw string.
 

C. Beaty

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Back in my techrep days, I observed that most F-86s had a yaw string attached to the nose hatch with a centerline painted on.
Pilots said they could get a few more knots of airspeed by keeping the string aligned rather than flying on instruments alone.
 
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wolfy

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A yaw string is the most important instrument on a gyro I reckon, when your doing a true vertical descent very close to the ground the last thing you want is an unexpected incipient spin from accidently going backwards. Only a yaw string tells you when you start going backwards.

wolfy
 

BEN S

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hmm...somehow this is copying posts I have no idea how or why.
I have never used a yaw string. I have flown in in rigs that had them but can't say I have ever bothered to look at them when flying.
To hear that you guys are putting such huge amounts of faith and importance in them somewhat surprises me.
Vance, to say you wouldn't fly a rig without one?!? "Hell, that's just crazy talk right there boy!"
 

WaspAir

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You really ought to try one. You may be surprised at how much more precision you can add to your flying with just a little bit of cheap yarn. Little slips and skids that you'll never notice on an inclinometer are really apparent with a string. With time, you can train the seat of your pants to be more sensitive as well (but keep the string).

I came to rotorcraft from the glider world, where nobody in his right mind will take off without one. A tiny misalignment or lack of turn coordination makes a huge difference in performance, because the sleek profile of a modern glider is defeated by slightly exposing a bit of the side surface and adding all that unnecessary drag. In a powered aircraft, you can gain a few knots at the same power setting simply by keeping the string centered.

If you were taught to "step on the ball" you may need a few minutes of adjustment to get used to the string indication; you need to use your feet to pull the free end of the string back to center. E.g., free end out to the left means apply right pedal to pull the string back to the middle; your airflow is coming from the right, so right pedal will align the ship with the flow.
 
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PAgyropilot

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Thank all of you for your replies. Today a friend took me up in his Champ, and I attached an RV level to the instrument panel, right under the Slip Indicator.



image_2021-04-06_195344.png

It turns out that the RV level, which costs less than $5, works better (is more sensitive) for indicating slip than a $110 Slip Indicator.
It works "opposite" to the standard slip indicator, in that instead of "stepping on the ball," you need to step on the opposite rudder
pedal to bring the bubble back to the middle. Works like a charm.
 
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