OSH slow flight practice

Frank Smidler · #1 07-10-2009, 09:07 AM

Yesterday my son Derek and I flew to Elkhart, IN to see Don McNamara and his RV-8 that is actually about to fly (YES, it is true, N8RV will fly). On the way home I thought it would be a good time to practice slow flight for our upcoming trip to OSH with N96FS. After hearing some of the stories of trying to stay in position behind slower traffic I wanted to know what I could do with the RV-6. We had full fuel and no baggage so it did not replicate low fuel, heavy baggage, aft CG we will have going to OSH but it was a starting point. I plan to practice again with realistic weight and CG conditions next week.

A little background, my RV-6 is light at 1009 lbs with a O-360-A1A and fixed Sterba wood prop. With the fixed pitch prop it doesn't slow down as quickly as a constant speed.

With no flaps we flew at 90, 80, 70, 65 and 60 kts. Even at 90 kts, in level flight the nose is up. At 60 kts it is sticking way up and would not be comfortable or safe on the FISK approach because you could not see forward at all. 60 kts in general was too slow and I don't plan to fly at that speed. If it comes down to 60 kts or circling back into the line, I will circle back.

10 degrees of flap was much better at all speeds but the nose still was up a lot at 70 and 65. With 30 degrees the pitch was much, much better at 80, 70 and 65 kts.

After this experience I plan to use 10 degrees at 90 kts initially. The 10 degrees of flap gave me a better pitch for visibility and will make it much easier to slow to 80 quickly with my fixed pitch prop. If I get behind something that I have to hold 80, 70 or 65 I plan to use 30 degrees of flaps for better pitch/viability.

How did others fly the FISK approach behind slower traffic?

scard · #2 07-10-2009, 09:35 AM

Quote:

Originally Posted by allbee

this kind of topic set off some thoughts. Lets say you do get sloooow traffic on the way in. I mean it can happen, they say 90kts, but I know some of those birds out there have a hard time doing that wide open. Can a person opt to just pull up to the higher altitude and run the 135kts into OSH. I'm heading to arlington tonight and my thought is if I run into a slooow runner in front, I'll just move up to the 135kts 1700alt and fly in and forget those slow birds.

The letter of the law in the notam says NO. If you can't maintain behind someone slow, but you CAN maintain 90kt, break off, go back to Ripon, and try again to find someone else to follow at 90kt.

Sid Lambert · #3 07-10-2009, 09:39 AM

I got stuck behind a Champ going in to Sun-n-fun this year. I switched the cruise control on 65 MPH with 10 degrees of flaps and powered through the heat. He even pulled away from me as I purposely gave him more room as we got closer to the runway. 65 MPH in a straight line at 1100' AGL is different than 65 MPH turning base at 350' AGL.

I plan on practicing for the worst before OSH as well though.

JDRhodes · #4 07-10-2009, 09:43 AM

Also - go to an unfamiliar airport and practice a tight pattern where you turn base to final over the approach end and touch down on a pre-determined point halfway down the runway - without dragging in low and slow and behind the power curve. Lots of people have problems with this, and it makes for bad landings, if you're not prepared.

painless · #5 07-10-2009, 09:59 AM

From what I have gathered from the Notam as well as reading the hints posted on the EAA site for VFR arrival to OSH, you are also allowed to rejoin the "conga line" should you have to break-off due to slow traffic. If there is an open slot, and you can re-enter the line without cutting someone off, this is allowed. Whether such a gap will be available is another question.

I too have been practicing slow flight and agree that 10 degrees of flaps helps with over the nose vis.

I would also recommend that close-in pattern practice is done. If you are directed to either 27 or the southern approach to 18, you will be required to make a close-in, low, base to final turn. This unfortunately is the aspect of arrival to OSH that claimed the lives of two on board during approach to 27 last year. Low fuel, aft CG and loaded to max, coupled with making that turn base to final lower and closer than you are familiar with can bite you.

What I have been doing is making my turn from downwind to base right at the approach end to the runway. Pick a spot approximately 1000-1500' from the approach end to simulate the orange dot for 27, or pink dot for 18 and practice nailing it. Make all your approaches as if you are going to be put down on the closest dot. Extending to the next dot is not too difficult.

I am by no means the "ace of the base", but I just hate to hear of guys stalling base to final at OSH. Practice that turn close and low, and hopefully we will not lose any of our fellow pilots this year to such an accident.

N941WR · #6 07-10-2009, 10:23 AM

Quote:

Originally Posted by scard

The letter of the law in the notam says NO. If you can't maintain behind someone slow, but you CAN maintain 90kt, break off, go back to Ripon, and try again to find someone else to follow at 90kt.

Or just start S-turning. You don't have to stay straight, just stay behind him.

BTW, your plane will handle differently in slow flight when loaded with all your "Stuff".

painless · #7 07-10-2009, 10:36 AM

Quote:

Originally Posted by N941WR

Or just start S-turning. You don't have to stay straight, just stay behind him.

BTW, your plane will handle differently in slow flight when loaded with all your "Stuff".

I don't recall if I saw it in the recent NOTAM, but the EAA site that explains the workings of the VFR approach via Fisk states that S-turning is not recommended. This is an excerpt from that site:

If you have to S-Turn in order to maintain the required ? mile In-Trail spacing, IT WILL NOT WORK! Check for other traffic and break off the procedure (turning left/right). Parallel the railroad tracks while proceeding southwest and find another aircraft to follow ? mile In-Trail.

JDRhodes · #8 07-10-2009, 11:01 AM

It does happen, but the chances of getting behind someone going 65 are fairly slim. The bigger risk is getting in front of some hot rod who thinks he (or she) needs to go 150!

Notwithstanding the occasional Cub and Champ, most little airplanes will fly 90all day long - which is why they picked that speed.

painless · #9 07-10-2009, 11:09 AM

Not sure about you guys, but my biggest fear is the arrival over Ripon. You have airplanes coming in from practically all points of the compass aiming for the same spot, near or nearing the same altitude.

Head on a swivel for sure!

Rick6a · #10 07-10-2009, 11:12 AM

Quote:

Originally Posted by Frank Smidler

How did others fly the FISK approach behind slower traffic?

Frank,

The scenario you describe is exactly why I am a fan and ardent supporter of any AOA system. Generally, I have no trouble dealing with slower traffic in the pattern other than to pay particular attention when someone flies in a unanticipated, non-standard or erratic manner. As I graphically showed a Zenith builder first hand during a demo flight just the other day, as long as I maintain an airspeed at or just slightly above the speed that excites the topmost red light on the AOA LED array to illuminate, the airplane simply will not stall. Intentional power off stalls are docile and my airplane stalls at 60 MPH IAS flaps up and 55 MPH IAS flaps down.....more than slow enough to deal with most bug smashers I may be joining in an en masse arrival near Oshkosh. I am convinced flying the AOA significantly increases the margin of safety. I'll leave it to others to debate what degree of increased safety that may happen to be.