Fuel Screwup Learned ON THE GROUND!

cavmedic said:
I'm afraid to turn the fuel valve off in the 150 I rent/train on because it feels so stiff, afraid it will brake in the off position.
Click to expand...
Same here: the instructor who checked me out in N2966V told me to disregard the checklists and not to switch the fuel off, ever. Breaking it off is a real possibility.

The fuel switch was one thing that I really hated about flying M20E. The "off" position there is between "left" and "right", so you have to pass it every time you switch tanks. The switch is also ridiculously stiff and also small. I was sweating bullets at every tank switch. Insanity, truly.

One of renters created a special tool: a crank fashioned out of a PVC pipe that permitted to switch tanks somewhat more easily.
 
I don't remember the Pipers I fly or have flown ever being in the OFF position. They are either right or left. All of the Cessnas I ever flew were always BOTH. Those were all rentals.
And it was following the checklist in the POH in an unfamiliar airplane that got me in trouble. It's hard to manage a book on your lap, follow the list, turn the pages, and keep it on track after you've dropped it once or twice. I can see why the schools all put it on a laminated card.
On the other hand, I managed to take the checklist home the other day. Didn't do the next guy any good, now did it?
 
silver-eagle said:
On the other hand, I managed to take the checklist home the other day. Didn't do the next guy any good, now did it?
Click to expand...
I always carry my own checklists. I get used to the layout of them and I switch to the the stock checklist I may slip and miss items.
 
Early in my lessons my primary CFI told me to create my own checklists - it's a habit I still do. Putting things in my own words makes me really read the POH carefully to make sure I don't miss anything and that seems to help me out with getting a head start on memorization.
 
kimberlyanne546 said:
Flaps down are the first part of my pre-flight, as soon as I walk up to the plane (Master On, Flaps Full Down, Check fuel gauge, master off). I put them back up at the runup.
Click to expand...
I do the exact same thing. Although, I always wonder why I'm looking at the fuel gauge when it's wrong 100% of the time and I'm going to stick the tanks anway. :dunno:

And in my club, 2xC172N's the tank position is always in both. I haven't found it in any other position.
 
numl0ck said:
And in my club, 2xC172N's the tank position is always in both. I haven't found it in any other position.
Click to expand...

Fuel on BOTH is in the takeoff and landing checklist. Very few people ever switch tanks in flight. I've tried it when I can remember on XCs to switch right tank because of the in-flight crossfeed issue. But it's really a minor issue and the fuel is feeding from both. When it gets below a certain level it will begin to equalize again. So that's why most poeple just leave it on BOTH.
 
airguy said:
I've had partial flaps stick on one wing on a rental 172 once, giving a heavy wing. On my own 172 now I always hit full flaps as I start my taxi, check them to make sure they are full down at some point during the taxi and then retract them, and visually check them for fully retracted as I start my mag check. If they are going to hang up on me or quit working, I'd rather know about it on the taxiway.
Click to expand...

kimberlyanne546 said:
Flaps down are the first part of my pre-flight, as soon as I walk up to the plane (Master On, Flaps Full Down, Check fuel gauge, master off). I put them back up at the runup.
Click to expand...
During the preflight the flaps go full down. After engine start, they go full up. I find it distracting and reduces 360 visibility during taxi to put them down.

The 172SP POH permits 0-10 degrees for takeoff. I've experimented with both settings and find that I preferred 10 deg but get a smoother and faster climbout a 0 degrees.
 
Jaybird180 said:
how can flaps kill?:dunno:
Click to expand...
Fail to deploy them, and on take off, you may not be able to lift off, and then you are going too fast to stop before you run off the end of the runway. This probably applies more to fully loaded commercial jets than your average single engine piston four-seater.
 
PPC1052 said:
Fail to deploy them, and on take off, you may not be able to lift off, and then you are going too fast to stop before you run off the end of the runway. This probably applies more to fully loaded commercial jets than your average single engine piston four-seater.
Click to expand...
Riiiiiiiiiiiiiiiiiiiiiiiiiiiiight
So do you think the primary CFI should have been harping on it?


Henning???
 
Skylane81E said:
Get them stuck down on the go, depending on the performance of the plane and the effectiveness of the flaps:hairraise:
Click to expand...

If flaps are stuck in the down position in the initial climb it would be a simple matter of returning to the field. Just like leaving the pitot tube cover on, eh?
 
Jaybird180 said:
If flaps are stuck in the down position in the initial climb it would be a simple matter of returning to the field. Just like leaving the pitot tube cover on, eh?
Click to expand...

At max gross, and on a high DA day, you may not be able to climb with full flaps.

Max gross climbs with full flaps at sea level, standard day is a certification requirement, however.

-Skip
 
Skip Miller said:
At max gross, and on a high DA day, you may not be able to climb with full flaps.

Max gross climbs with full flaps at sea level, standard day is a certification requirement, however.

-Skip
Click to expand...

Why would someone get themselves into this position in the first place? If your aircraft uses takeoff flaps, you select that and no more. If they do not retract on climbout then you return to land.
 
> Why would someone get themselves into this position in the first place?

Go around ... due to animals, opposing or crossing traffic, obstruction, etc.
 
rainsux said:
> Why would someone get themselves into this position in the first place?

Go around ... due to animals, opposing or crossing traffic, obstruction, etc.
Click to expand...

What aircraft may be at risk for this scenario? Underpowered with full flaps?
 
You don't have to be at Max Gross around here in the summertime for full flaps stuck down during a go-around to become a full-blown emergency in most small singles.

With summertime mid-day DA approaching 10,000', you've got a serious climb problem on your hands.

In the mountains at 75F at even non-"one-way" airports, heavy, with flaps stuck at full, it's a guaranteed emergency.

Best keep those slow flight skills sharp and the turns coordinated and shallow.

C-150/152 are often grounded in the hottest days of summer outside of early morning and after sunset. C-172 is the trainer needed for two plus reasonable fuel during the daytime.
 
Jaybird180 said:
Fuel on BOTH is in the takeoff and landing checklist. Very few people ever switch tanks in flight. I've tried it when I can remember on XCs to switch right tank because of the in-flight crossfeed issue. But it's really a minor issue and the fuel is feeding from both. When it gets below a certain level it will begin to equalize again. So that's why most poeple just leave it on BOTH.
Click to expand...

The only time I'll use left or right in a plane with both is if I have a heavy person on one side that I want to balance for.
 
Jay,

The flaps thing was probably meant to apply to airliners or other, larger a/c that normally take off with flaps extended. Although as someone pointed out, departing with full flaps and a combination of a heavy plane and or high DA can result in the inability for a GA plane to climb. Fortunately the plane is slow and the flaps move quick so the attentive pilot will hopefully be able to fix a mistake here.

Airliners need a bunch of flaps on takeoff, because they are so slick when clean. A heavy airliner that rotates and notices he forgot to put the flaps down is in big big trouble.
 
Last edited:
Flaps can cause problems for a lot of planes on take off, either too much flap or not enough. Citations use 15* actually T/O-approach flaps for take off, lengthens the ground run considerably with zero flaps. I had a pilot take off in my old 414A with 5 men on board, warm day, luckily at sea level with FULL FLAPS:yikes::yikes: Good news is both engines ran fine, bad news is they didn't discover it until they were above 5000 feet!:mad2: The switch was in the up position, but the flaps never moved after landing, recycling the switch moved the flaps up and the plane picked up speed pretty quickly. :D
 
That's why I visually check flaps at takeoff. But I can do that in a high wing.
 
This will tie back to the checklist bit of this thread in a minute. Bear with me please.

Today I took a 152 out with a squawk indicating an malfunctioning radio that was flashing and powering off (amusingly the sheet also said "the engine almost quit 3 times" /boggle). Mechanic checked it out and ran it around the pattern with no problem. Keep in mind that I had this aircraft for over an hour yesterday and also had no problem. Figured the guy from yesterday didn't know that the avionics were not connected to the engine and just assumed that the aircraft was about to fall out of the sky due to the radio issue....

Mechanic gives me the plane back with the all clear and I start my takeoff roll. Note that like an idiot I figured I already did the preflight just before the mechanic took it and and didn't need to do it again. I notice that this thing really wants to get off the ground and started to lift at 40 knots. I started forcing the nose back down into Vx and swearing at myself.

Of course, the mechanic landed with lots of nose up trim which I did not correct for takeoff =P

Checklists good. Assumptions bad.
 
Oh and incidentally the radio failed as soon as I left the pattern, and I had to return to get a new radio :)
 
Very few airplanes have enough fuel in the system downstream of the shutoff valve to enable a takeoff. It might idle for some time with the fuel valve off, but takeoff fuel flow is much higher than cruise flows and the system simply can't provide it. The fuel strainer will not empty itself to provide the fuel, either, since its fuel enters the top and also exits the top. None of them exit the bottom; that's reserved for water and dirt. The only way to get fuel out of the strainer is to allow fuel into it. The shutoff valve is usually right near the firewall, so we have the fuel that's in a 3/8" or half-inch line about two feet long, and the fuel in the carb bowl. Neither of those amount to more than a couple of cupfuls and won't satisfy an engine that wants as little as seven gallons an hour at full throttle. That's a gallon every eight minutes, a pint a minute. The engine should quit in the takeoff roll, if not sooner.

The sticky 150 valve hasn't been taken out, disassembled and lubricated. It's a plain old tapered plug valve that requires a fuelproof grease like Fuel Lube. The grease gradually works out of it and the brass parts start seizing. This will continue until the handle or shaft breaks off, and then things get expensive. There's nothing like good maintenance.

Conical_plug_valve.PNG


0411803-5_014.JPG


Dan
 
Old Thread: Hello . There have been no replies in this thread for 365 days.
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.
Back
Top