Shaun Evans

Hi,

I had an unfortunate occurrence the other day at the flying field. I had a flame-out (on a high-speed, down-wind, low pass of course) with my Yellow F-15. My timer was set for 8 minutes as usual, and I usually land with 1/4 to 1/3 left in both main tanks. The flame-out occurred with just over a minute remaining on the timer. Luckily, I was able to do a climbing tear-drop turn and bring her back to the runway with only minor damage to one main gear mount. Upon landing, ECU says fuel and the tanks were as dry as the Mojave.

Here's the question: How much fluctuation have you guys seen in fuel consumption between flights on cold days versus hot days? How about altitude changes? I know there are fluctuations, but how much? I should note that this was a 'high altitude' flight, whereas none of the other 8-minute flights with fuel to spare were.

Thanks in advance for your input.

Thud_Driver

My Feedback: (1)

I usually fly at Rabbit dry lake, elev 2800'. When I go to someplace like Sepulveda, I have to shorten my timer to account for higher fuel comsumption at the lower elevation. So, if you were at a higher elevation than normal, you should have had, generally, less thrust, less fuel consumed, and less performance, i.e., longer takeoff, less vertical, faster landing. You may or may not have noticed any of that depending on the weather & elevation change.

Maybe something else happened. For instance, on my JR XP9303, I used to use the button to activate smoke. However, everytime I had the smoke on, it turned the timer off. Couldn't defeat the button being tied to the timer and luckily, I didn't crash before I figured it out. Anything new tied to the timer??

tp777fo

My Feedback: (28)

They always flame out downwind and low, it's called "Murphy's Law". The left stick timer controller does the trick for me.....forward on the stick the seconds tick off quicker, low left stick seconds last longer. I know what you mean though, I have found wide variations of fuel remaining when I thought I flew the same as last flight (or so I thought). I have had 2 flame outs with Raptor lately, glides quite nicely for a heavy jet. Still trouble shooting problem.

Shaun Evans

Hi,

Yeah. I ran the airplane through a whole tank of fuel on the ground at full throttle (with a few cycle-ups) on the deck. I used that as a starting point for my timer. When I flew with a 7-minute timer, I'd land with half-full tanks. So, 8 minutes it is, and since the engine is on the lower end of the spec for the plane, I spend a lot of time at full-throttle. I've had a few flights where full-throttle was the setting for 90% of the flight, and have about the same results. My 'high altitude' flight wasn't at a high-altitude field, it was just a very-high-altitude flight (for the benefit of the on-board camera) and I'm wondering if that had anything to do with it.

KC36330

for me at least, the flame outs come when the left stick is held in the ON position for too long during the said flight. of late i notice i keep it there more often then not so i have readjusted my timers accordingly. I'd say chances are you held it there for longer then you usually do as well.

rcjetsaok

My Feedback: (7)

Not to sound too stupid, but it is it possible the tanks were not full when you took off ???? I have done that before on my old DF F-15.... Mine didn't go 3/4 of the timer... It flamed on the first lap. Forgot to fill it up...[X(] I have refueled my turbines before and my Jersey ran out of fuel in mid-fuel, had to mix another jug. I almost forgot to finish fueling before I started. It's not hard to do if you get distracted.

Danno

tp777fo

My Feedback: (28)

Danno, was that the time you put french fry oil in the fuel?

rcjetsaok

My Feedback: (7)

NO!!!... You just go back doing before you decided to give me kaka!!!!!
D

Erik R

My Feedback: (32)

Shaun,

Another,more likely possibility is an undetected fuel leak.A density altitude change of even 2000 ft shouldn't change your fuel consumption that drastically.A leak that doesn't show in a static enviornment,will surface under a pressure/suction enviornment with the fuel pump running.Good luck.

Erik