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-   -   Forward slips in the 9A (https://vansairforce.net/community/showthread.php?t=137958)

flightlogic 05-18-2016 01:31 PM

Forward slips in the 9A
 
This thread is a drift from the video of cross controlled approach that is being viewed by many.
I practiced a few forward slips the other day at about 80mph indicated. The RV does not really show much of an appreciable sink rate increase... when I have the rudder to the floor. If I let the airspeed decay (as tested with Ed Wischmeyer the other day) the sink rate can get away from you.
I used to love slipping the Luscombe, which had no flaps.
The RV shudders quite a bit... but does not give me much sink in a slip.
Am I missing a technique I should try? All comments welcome.

luddite42 05-18-2016 01:40 PM

Quote:

Originally Posted by flightlogic (Post 1080151)
Am I missing a technique I should try?

Nah, the short wing models aren't much better...at least if you're accustomed to slipping antique/classic/aerobatic airplanes with lots of drag and powerful rudders. RVs are somewhat rudder limited compared to other types, and just don't have much drag to exploit in a slip.

flyboy1963 05-18-2016 02:23 PM

one guys opinion
 
so I am no test pilot, but an observation or two.

If I am high on approach, full flap idle glide is VERY speed dependent.
not having calibrated it, something like -500 fpm at 70 kts, -600 at 65 kts, and -900 at 62 kts.!!!!! ( estimates)
the nose is pretty high, and it requires attention to hold that rate.

my forward slip is MUCH more nose down at 70 kts....and I can see my aim point on the runway, so that's the main benefit.
Left leg gets tired if I'm having to hold the slip for very long!....the big rudder really pushes back, and yes, there is bumping and rumbling as it's in the dirty air swirling behind the flaps I suppose....but it IS coming down at a good rate, or perhaps, a better angle?

sblack 05-18-2016 03:15 PM

I wonder how close to stall you are getting with full rudder at 62 kts? Not only does stall speed go up in sideslip, but the characteristics would be sporty i.e. that would be a spin entry - in what direction I don't know. I was always taught, by a very good pilot of aerobatic, antique and classic light planes (cubs, champs etc) that in a slip you always want to have the nose below the horizon - have lots of green in the windshield, not blue. He had lots of RV time as well, but I don't know if he intended that advise for the RVs as well. So really slowing it down and then putting in full rudder - I would want to try that up high first. Full disclosure I don't have much RV time yet.

simpkinsona 05-18-2016 03:23 PM

Just right
 
Quote:

Originally Posted by flightlogic (Post 1080151)
This thread is a drift from the video of cross controlled approach that is being viewed by many.
I practiced a few forward slips the other day at about 80mph indicated. The RV does not really show much of an appreciable sink rate increase... when I have the rudder to the floor. If I let the airspeed decay (as tested with Ed Wischmeyer the other day) the sink rate can get away from you.
I used to love slipping the Luscombe, which had no flaps.
The RV shudders quite a bit... but does not give me much sink in a slip.
Am I missing a technique I should try? All comments welcome.

Somewhere between "not much sink" and "sink rate getting away from you " is the right speed for a slip. For me it's about 65 kts. This is one of the things I really like about the 9, you can slow down and sink like a rock or speed up and stretch your glide even into a stiff wind.

luddite42 05-18-2016 03:28 PM

Quote:

Originally Posted by sblack (Post 1080168)
Not only does stall speed go up in sideslip, but the characteristics would be sporty i.e. that would be a spin entry... I was always taught, by a very good pilot of aerobatic, antique and classic light planes (cubs, champs etc) that in a slip you always want to have the nose below the horizon - have lots of green in the windshield, not blue.

I've never been able to spin an RV from a full deflection slip if you ease the stick all the way back. If you yank the stick sharply from high speed, you could snap/spin, but if you just simulate "creeping hand" syndrome from a full deflection slip, it's spin resistant. Most airplanes behave this way.

scard 05-18-2016 03:37 PM

I've never been able to get the -9 to do anything interesting with full rudder deflection and the nose at the horizon or lower. It is useless to slip at too high of a speed where you'd be better off to slow down and get way behind the curve where it really starts to come down. I see it often "Why won't it come down?" "Because we're honkin' along at 70kts."

alpinelakespilot2000 05-18-2016 04:08 PM

At about 60-65 KIAS (1.5 Vso) I think the -9 fwd slips full flaps very well. I do them all the time to make adjustments in the glide path.

What I do notice is that my airspeed doesn't read very well in full slips, so I have to do them a bit faster than my normal approach speed. If I aim for 60-65 KIAS in the slip, by the time I straighten out the airspeed is showing 55-60 KIAS which is approaching what I normally try to be doing short final at anyway.

In short, big fan of full flap fwd slips in the -9.

flightlogic 05-18-2016 06:26 PM

9 model forward slips to land
 
Sounds like I need to try a few with slower speed. I know on most slips... kicking the nose straight at 50 feet settles the sink right back to normal for the round out.
If you hold an RV into a forward slip until that height... does it flatten out the glide path when you pop the nose into alignment with the runway?
I have tried simulations at altitude... but I just can't tell much. Not enough visual cues and references to be of much use.
I remember a thread where Allen of RV fame... let a Pax land. He got too slow and did not add power when told to. The gear got damaged.
I want the most performance, but don't want to tread in the danger zone.
Have not had any dual in the plane. Just bought it and taught myself.

rockwoodrv9 05-18-2016 06:54 PM

Nick,
Do you have any aerobatic training? Maybe I am just freaked out because of watching how quickly the plane went around in the other video. I never wanted to do aerobatics but I have become very interested in getting some spin training in the future! I have no trouble slipping the 172 or Archer I am taking lessons in. When I do transition training, I sure want to master that skill before I try it myself!


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