Flight planning with Vcc?
I've had my Private for less than a year so please be kind. Maybe I'm missing something obvious, but...
I have an older C182 with no auto pilot. On longer xc flights I like to climb to 5000 MSL at Vy (23"MP & 2450RPM) and then transition to a cruise climb (Vcc) of about 90 kts. Up to 7500 MSL this gives me a climb performance of just over 500ft/min and 21 gal/hr. Once I reach cruise altitude (7500 to 10500 or so) I dial it back to MP & RPM settings that give me better gas mileage at 130-ish kts. Any suggestions on how best to plug these Vy, Vcc and cruise settings into SkyVector, AOPA iflightplanner, or any of the others?
Comments
Once above pattern altitude why not use cruise climb all the way to your cruise altitude ?
Vcc = Vy + [Vy-Vx]
In my C175 I use 100 mph and still get 700-800 fpm.
Vcc gets you a good airspeed with little loss of roc.
Thanks, Jim. At my home airport I prefer to do an extended climb at Vy to get over local mountains, etc. ASAP. My POH climb tables are limited to performance at full throttle & prop which burns too much gas. So, starting with the POH climb & cruise tables I used spreadsheets, simple linear interpolation, scatter charts, trend and curve fitting functions to generate performance equations that give me my own cruise-climb performance tables at 2450 RPM & common MP climb settings. Took lots more time than it should have but now when I use SkyVector or AOPA iflightplanner, etc., I plug in my new 90kt Vcc, Vertical speed and fuel flow settings in the app's climb performance fields. Seems to be working for me. We'll see.
Hi 93066......
Congratulations on your relatively new certificate and aircraft ownership!
ForeFlight offers basic and custom aircraft profile options for fuel burn/HR, TAS, FPM, in cruise, climb, and descent phases of flight for multiple aircraft. If you have not used ForeFlight, they have a free trial period. It is an incredibly useful program for flight planning, navigation, and reference. Yes it is by subscription after the trial but if you can swing it for 1 year, I seriously doubt you will regret the choice.
It does require an iPad but you can even purchase a refurbished iPad mini directly from Apple with warranty. I use a mini right on the yoke (MyGoFlight mount) and it is a perfect solution for me. If you do try this route, you should purchase an iPad model with cellular capability. You do not have to activate the cellular feature, but the hardware includes a very good built in GPS receiver.
Regards,
Mike
Thanks, Mike. I've test-driven ForeFlight and will probably get my own subscription someday (rather than mooching off of my daughter's account). My original post should have said that I was looking for a way to enter multiple climb settings (Vy transitioning to Vcc) into any of the popular flight planning tools.
What do you do? Do you plug in Vy into your planning tool climb settings and fly Vy all the way up to cruise?
Plug in Vcc for your climb settings and fly Vcc up to cruise?
Something else?
In my case, my Cherokee burns an average of 10 GPH no matter what I do! So to be honest, I really just enjoy the view out the window! I quit worrying about advanced fuel planning and how much fuel I could save in the climb or how many miles per gallon I will get. I will lean of course. I always depart with enough fuel plus reserve for the flight, a personal limit of 3 hour legs, and fuel always available at those stops, it is not really an issue for me.
But, I do keep an eye on engine temps and modify my climb speed based on that. I usually climb initially at Vx or Vy as appropriate, but if the climb is going to take more than five or so minutes, I'll just go to 100 mph indicated up to cruise altitude for a cooling/speed compromise and shoot for 65 - 70 % power RPM with my fixed pitch prop when I level off.
Regards,
Mike