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Thread: Slip Speeds

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  1. #1
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    Default Re: Slip Speeds

    You have AOA on the G3x correct? I find it to be very helpful and the best tool. I am focusing more on the AOA and not the speed. Being nervous at the slow speeds is what you should be. Coming in steep, your speeds can be less because your AOA is less but you will run out of airspeed quicker on the flare. I think this is where most blip the throttle to help you arrest the decent??? I am no means an expert and trying to get the landings short also. Coming in over an obstacle adds significant landing distance. I have a field by my house that is 600' long. (641' according to google) I have a adjacent field to that, that I can use for an approach. There is a 4' fence separating the two. I can consistently land sub 300' but I am nervous about landing in that field. So for safety I am calling my landing distance 300' for no obstacle. Best I have done so far is 200' hard braking. First unknown is its grass so I will have reduced braking. (Don't want to land with it wet or frozen) Second, I have to clear the 4' fence on the one end. I figure I will be 10' agl coming in over the fence for safety. If I do the math on that, 3 degree standard approach and cross the fence at 10' that ups my landing distance 190'. If I cross the fence at 10' and fly a steeper approach at lets say 5 degrees my landing distance goes up 100'. I don't know what factor landing on grass will have compared to the landing distances I am getting on dirt, but I am getting close to 600' now.

    So doing the math on yours.......crossing obstacle at 100' and 3degree approach angle you are adding 1908' to your landing distance.(I guess high-school math is useful?) If you go twice as steep and come in at 6 degrees 100' over the trees you landing distance increase is 951'. So even coming in steep crossing a obstacle adds significant distance.

    I feel like when I slip I need to double my approach angle to keep the same AOA. (This is power at idle. I like landing with power at idle so anytime if I lose an engine I will make the landing. Maybe this is not the best way to land short though? May need to be under power to get the slower stall speed??) I find if I get setup on the AOA I want, then slip, I must push forward fairly hard about doubling my approach angle, then when coming out of the slip I will have the energy needed to flare.
    Last edited by Shadowrider; 02-05-2020 at 09:32 AM.
    Dustin Dickerson

    Building 7ss STI x 2
    Oratex
    29" shock monster
    EP912STI 155hp
    Garmin
    N33TF......FLYING!
    N53TF......FLYING!

  2. #2
    Senior Member JoeRuscito's Avatar
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    Default Re: Slip Speeds

    Dustin I really appreciate you thinking on this and the time your taking to explain your methods.

    I do have AOA and I certainly use it in all cases to make sure I still have lift available, although I imagine like airspeed it is less reliable in a slip when the wing shadowed by the fuselage no?

    I have noticed when I slip, if I keep my airspeed consistent to a normal approach (50-55) which seems to be a similar sight picture angle, When I remove the slip at around 10ft I find I seem to have even more energy causing my float to extend. Im also at idle.

    Its interesting to fly with my friends (in a pacer and a clipper) and watch them come over obstacles, they drop like rocks! Almost vertical. The kitfox glide puts me at least a couple hundred feet past their touchdown (without a slip). Hence why I want to get better at slips.

  3. #3
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    Default Re: Slip Speeds

    No worries as I am trying to figure it out also. Yeah I think AOA has errors when slipping. Maybe others with chime in, but sounds like you just need to reduce speed when in the slip. Maybe focus on what your speed (AOA) before and after the slips? Maybe you need to slip harder? I have just been trying to baby step slowly reducing speeds. Our aircraft drag is much different so others running grove gear and 7ss wing will probably be the most helpful. I feel like I drop like a rock if I want.
    Dustin Dickerson

    Building 7ss STI x 2
    Oratex
    29" shock monster
    EP912STI 155hp
    Garmin
    N33TF......FLYING!
    N53TF......FLYING!

  4. #4
    Senior Member Flybyjim's Avatar
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    Default Re: Slip Speeds

    Shoestring is where I first learned to fly with Larry Johnson. My farm airfield is 0PA2 just north of Carlisle, Pa. N94 My field is 1200 long 100 foot wide turf. I am flying a Rans S7 at this time building the Kitfox SS7.
    Does your airfield have a # to locate?

  5. #5
    Senior Member JoeRuscito's Avatar
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    Default Re: Slip Speeds

    Thanks for all the input guys. I did some practice this weekend (calm winds). 1.3 over stall speed in that configuration feels good and reducing to 5 mph below makes my decent rate feel much more like I remember at stick and rudder, these speeds are similar to what I had found was my best sink rate with no slip. For reference my speeds are: 1 notch of flaps stall=44, 1.3x=57, over the threshold = 52 --- full flaps stall = 39, 1.3x=51, over threshold = 45. These numbers give me plenty of flare authority but little to no float. This was similar to my experience at S&R, where they taught to fly right down to the runway, little to no round out and right into a flare/touchdown. This worked great for calm winds for me, but Im still hesitant to be so slow... Still lots to learn...

    I may order up some VGs to see how they do.

  6. #6
    Senior Member fastfred's Avatar
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    Default Re: Slip Speeds

    Those speeds sound pretty similar to my 7. Although I had the 45 over the numbers bite me hard one calm day .I would rather have some head wind and below 50 is out of my comfort zone anymore without some power. good info

  7. #7

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    Default Re: Slip Speeds

    Bringing this thread back to life....

    Wondering if others have had this phenomenon and/or could help me understand it better:
    I took my model V up to 5000' to practice deep slips. (My V is setup up like a model 7 with the larger elevator, speedster tail, and longer nose) My CG was at 11.2, weight at 1123#. I applied full flaps, full right rudder, and dropped the left wing.. all seemed like a normal slip. However after about 5 seconds in this configuration, the rudder pedal lightened up and the control stick lightened up, a control reversal I believe? The plane seemed to be getting deeper into the slip after this happened- Yawing further to the right, left wing dropping more. I immediately took it out of the slip which took some force on both the pedal and and stick.

    I repeated the test again with the same results. Essentially I could let go of the controls and the plane would stay/deepen into the slip. I did not see how far it would continue to go into the slip like this.

    Is this common on the kitfox? Has anyone else had this happen? Maybe my procedures are wrong? Thanks!
    Kitfox V building
    "Be Quick, Be Quiet, Be on time" -Kelly Johnson

  8. #8
    Senior Member Dave S's Avatar
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    Default Re: Slip Speeds

    T,

    What was your airspeed before initiating the slip?

    Assuming engine at Idle or did you have some power in?
    Dave S
    Kitfox 7 Trigear (Flying since 2009)
    912ULS Warp Drive

    St Paul, MN

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