Slips - with and without flaps

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T-6pilot
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Re: Slips - with and without flaps

Post by T-6pilot »

Dan H.
The "No slips with flaps extended" is a restriction on the older Cessnas with >30deg of flaps available. Slipping with flaps extended could disrupt airflow over the horizontal stabilizer....That's bad! Not really an issue in a low wing plane.
Simeon

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Re: Slips - with and without flaps

Post by PlaneDan »

Dan W.

Thanks for the detail. I expressed concern because I remember that during my flight training in Cessna's, I was told that slips with flaps were not allowed.

That said, if you are willing to conduct my first flight, I will get you put on the insurance, today.

Dan H.
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Re: Slips - with and without flaps

Post by RonFranck »

Great information, Dan. I'm going to print this out so it's always close at hand. :idea: :idea:

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Re: Slips - with and without flaps

Post by danweseman »

All
First, in general slips with full flaps have been fine in the 4 Panthers I have tried it in. I would use caution and try this at altitude during your flight testing. When slipping make sure speed is under control before slipping. If needed raise the nose a bit to slow the airplane then as you attain the desired AS start slip and lower nose to desired glide slope. Always slip into the wind and consider that extended slips may unport your fuel pick depending on direction, so select the appropriate tank on down wind. I personally restrict my slips to 10 seconds or less,although in testing over done 30+ seconds at idle with out losing fuel pressure.

In general "it is hard to slow down" is really kinda a two part issue. Not slowing down easily, and needing to slip on final are two different issues. slowing down as you enter the pattern and getting airspeed under control early on are key to having a proper glide slope and AS under control during final approach and flare.If you fail to get AS in the desired range early you will struggle with being hot or high the rest of the approach.
on your first few flights you need to make sure you fly off a long runway with fairly clear approaches. You may have a ASI failure or it may be considerably inaccurate so you need to have some plan to quickly verify the AS is close on your first flight. Having flown or witnessed/ been involved with close to 50 first flights, instrument error, both engine, and AS is the #1 issue.On the first flight of N515XP i had a complete ASI failure shortly after lift. Not a big deal as i had GPS ground speed and chose a cool morning (no DA) with no wind so it was my GPS GS was very close to true AS.

Once you have calibrated your ASI you should get the AS under 80 MPH before entering down wind. You want 75 MPH or less before you lower the nose at all. If not you will chase AS the entire pattern. The airplane WILL slow down IF you do not lower the nose. With the engine is near idle simply raise the nose until the AS is under 100 MPH and the use full flaps. keep the nose up until you are under 75 mph IAS. Then you can lower the nose a bit. actually you will basically be level, not nose down. The Best L/D is around 85-95mph ,so you want to get it much slower to increase the induced drag.
75 MPH CAS is about 1.3 times clean stall speed and offers plenty of margin over stall. I typically fly final at 70 MPH for wheel landings and 65 for 3 points (i prefer 3 points in general but that is pilot preference. )

I have watched at least 25 other Panthers do landings, and honestly most pilots fly considerably faster (10-15 mph) than needed ,and do a wheel landings to recover . Its pretty easy to stop in 1500 ft over a 50 ft obstacle if flown correctly. I see a lot of Panther landings and have noticed that using 1500-1800 ft of runway is common (2500 ft or more over a 50 ft obstacle) , but is totally unneeded.

These numbers assume a calibrated ASI.

Again if you start the approach on down wind at 75 it will be a lot easier to judge the pattern size and glide slope. If you are to fast as you start to turn base you will struggle with AS the rest of the way around, and then you will complain about it being "hard to slow down".

Dan , this is not the first time you have shown concern for this "issue". I would strongly recommend you get a very experienced pilot to conduct your first few flights.
Dan Weseman
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Re: Slips - with and without flaps

Post by PlaneDan »

Thanks. I have a 3B Whirlwind and am with you on that other info as well.
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Re: Slips - with and without flaps

Post by rv10builder »

I switched from a two blade fixed pitch to a three blade FP expecting the Panther to slow down, but the change was minimal. I still find myself slipping the airplane on final with 20 deg flaps and an airspeed of 70 kts. That being said, I’m not inclined to change that much because a) I like slipping, b) don’t want to go slower, and c) tend to fly a tight pattern.
Brian S.
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SPA Panther Sport S/N 087, O-320-B2B (160HP), Catto 3-Blade, GRT Mini, flying 100+ hours
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Slips - with and without flaps

Post by PlaneDan »

I am interested in getting some information on slipping to a landing, with and without flaps.

I am hoping to not need to slip, but I have read about the Panther's reluctance to slow down.

I had to slip my KR on every landing until I added a speed brake.

Thanks in advance.
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