It's been a long time since I've posted (or even read the forum) because I've been stuck here in Singapore for two years and my building is put on hold.
However, the bug is still there and I do flight planning every single day (and studying for my IFR). I really want to take my RV (if it's ever finished) around the world to show her off.
One thing has been bothering me. And I'd like some input.
Many RV's have made the really, really long hop from Hilo, HI to Santa Barbara, CA (+2000NM) which equates to roughly 15 hours of flying time at 55% power. Now.. here comes the sticky part.
The useful weight of an RV-7 or RV-9 is under 600 lbs (even less kitted out for a global flight). If a pilot weighs in a 165 lbs and he has 30 lbs of kit (clothes, survival gear, a sandwich) that leaves only 435 lbs for fuel and oil before approaching Gross Weight.
Now, that equates to just over 60 gallons of fuel (45 in the wings and a ferry tank in the PAX seat) and with a burn rate of 6.5 GPH at 55% that give you just under 10 hours of flying (no reserve) -- a rough cruise speed of 150 knots at that speed give you a range of 1420NM OR about 600NM of swimming.
Jon Johansson did this in the RV4 by taking on a LOT of extra fuel with a ferry tank in his rear seat and wing tip tanks. But even a cursory look at the RV4 specs gives me approximately the same mathmatical problem.
So --- here it comes -- how do they do this? Are my performance figures 30% off -- OR -- are these long flights done significantly over Gross Weight.
I still have my lessons in my head about flying within the operating envelope and I'm still new enough to do a W&B everytime I take up a rental (even if I'm solo). I read about pilots going over GW all the time (as long as it's balanced) without problems.
Can anyone give me insight to this thorny issue?
Thanks!
However, the bug is still there and I do flight planning every single day (and studying for my IFR). I really want to take my RV (if it's ever finished) around the world to show her off.
One thing has been bothering me. And I'd like some input.
Many RV's have made the really, really long hop from Hilo, HI to Santa Barbara, CA (+2000NM) which equates to roughly 15 hours of flying time at 55% power. Now.. here comes the sticky part.
The useful weight of an RV-7 or RV-9 is under 600 lbs (even less kitted out for a global flight). If a pilot weighs in a 165 lbs and he has 30 lbs of kit (clothes, survival gear, a sandwich) that leaves only 435 lbs for fuel and oil before approaching Gross Weight.
Now, that equates to just over 60 gallons of fuel (45 in the wings and a ferry tank in the PAX seat) and with a burn rate of 6.5 GPH at 55% that give you just under 10 hours of flying (no reserve) -- a rough cruise speed of 150 knots at that speed give you a range of 1420NM OR about 600NM of swimming.
Jon Johansson did this in the RV4 by taking on a LOT of extra fuel with a ferry tank in his rear seat and wing tip tanks. But even a cursory look at the RV4 specs gives me approximately the same mathmatical problem.
So --- here it comes -- how do they do this? Are my performance figures 30% off -- OR -- are these long flights done significantly over Gross Weight.
I still have my lessons in my head about flying within the operating envelope and I'm still new enough to do a W&B everytime I take up a rental (even if I'm solo). I read about pilots going over GW all the time (as long as it's balanced) without problems.
Can anyone give me insight to this thorny issue?
Thanks!