Flying the Waco YMF-5C Biplane
Treated myself yesterday to a flight in a (new production - 1994) Waco YMF-5C biplane.
I've flown several examples of the Waco UPF-7 biplane in Key West over the decades, which frankly were trucks to fly, at least compared to a Stearman.
UPF-7's were built before WWII and had the familiar Continental W670 220hp radial engine, and were also known as the PT-14 in the USAAF.
The "new production" YMF-5C and YMF-5D Waco biplanes have the 275hp R-755B Jacobs radial engine with a wood fixed-pitch prop, so no gyroscopic coupling in yaw/pitch when you raise and lower the tail - nice. Easy to keep straight on the runway!
I am a stranger to the Jacobs - never flown a C190/C195 - so I was looking forward to flying one.
The YMF-5C (forgot to take a picture) looked identical to this one:
A cream/red paint scheme. Unfortunately they used urethane instead of nitrate/butrate so the usual cracks in the paint at the inner ribs cannot be easily fixed :-(
Had four ailerons, and stick forces were light.
Open cockpit, of course. Removable stick in the front cockpit which can carry two in the front, which is why the Waco is a favorite with people doing rides.
Pulled the prop through to get rid of lock, started easily. Running 25w60 but still idled for a long time – on my dime, I might add - until CHT came up to 250F.
Ignition was weird. One side was a buzz box (for starting, probably with a retarded set of points), the other side a magneto.
Even with negative density altitudes, the YMF-5C did not leap off the ground. Climbed out at 80 mph indicated, which gave around 500 fpm.
Carefully watched the carb temp, kept it at +5C or slightly higher. Jacobs can ice, I am told.
Levelled off at 3000 feet and cruised at 105 mph indicated and 1900 RPM to the practice area. Coarse prop - not easy to overspeed.
Slow flight required amazingly little right rudder. Didn’t expect that.
Even a full-power stall was almost "feet on the floor"!
Did some light acro. Did nice 90 degree wingovers, with opposite aileron and lots of rudder past the apogee.
Instructor insisted upon demoing the first landing, which he pooched. Flared at around 10 feet. I resisted the incredible temptation to ask him if I should do the same?
My turn. As a Pitts guy, I turned base WAY too soon and even with power idle and terrifying the instructor with a full-rudder sideslip to kill airspeed, I was much too fast over the threshold - closer to 100 mph instead of the 90 mph he recommended, and the 85 mph I ended up using later. Fixed pitch prop has NO drag compared to constant speed prop. Need to remember that!
Anyways, no problem. 6000 feet of pavement, nice wheel landing. Instructor did NOT like the forward stick in the wheel landing to keep the tail up, despite his pre-flight warning that the tailwheel shimmied. Odd.
Turned base a bit later, next one worked out better. Weirdly enough I could fly a straight
in final at 90 mph and see forward over the nose - no slant final. Probably because we
were approaching much too fast, IMHO.
I love wheel landings!
Last landing, slowly brought the tail down and NOW the runway disappeared, and it
was all peripheral vision. Keep the picture the same on both sides!
Taxiied in. What a nice airplane! As I was coming in, another Waco (UPF-7) was
taxiing out. New production, I was told, not pre-WWII. Gorgeous, shiny and clean.
Lots of chrome on that radial engine!
And what a great day. Rode the CBR600RR to and from the airport, through the hills.
This meant, of course, that I was flying an open cockpit biplane with my Joe Rocket
leather sportbike jacket - not exactly period correct - but the Waco didn't seem to mind.
In fact, it was warmer in the open cockpit Waco, than it was on the 600!
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acboyd@gmail.com
Dec 2015