Preflight Checks, What do you find?

[Old Koreelah]

...Pilots should practice a circuit with no ASI preferably with an instructor. Over the years I have seen a few ASI failures and experienced several myself. It is not a dangerous situation if you are aware and trained for it. Nev

Flew for months with a sus ASI without a problem, by referring to attitude and feel. That meant always erring on the quicker side of caution, so my landings were fast and long. Have since had the instrument checked and recalibrated, so need far less ground.

 

 

[Sapphire]

Thats ok unless you are flying a C5 Galaxy or similar. Requires about 12000 feet to take off and that is probably at ISA sea level. It wont be flying to Bangda airport[worlds highest] in Tibet too often- 15000 feet plus. The terminal must be pressurized there.

 

 

[Sapphire]

I'am thinking.........

 

 

[facthunter]

I have never checked an ASI by blowing in it in my life nor have I ever thought about doing it. Disconnecting the lines and blowing through them might be a posibility for some checks. You should only check for Pitot blockage as far as I am concerned as a pilot and that applies to the static ports too. Some installations may be subject to water getting into them and have a procedure for draining them.

 

If your system has the static source inside the cockpit it will under -read the slow speeds and over-read the high speeds.

 

Once you are used to the speed your ASI reads It would be suitable ( for you) but not the thing to expect when a school plane or lent to someone. having the ASI and altimeter too as accurate as possible would be the aim. There is an allowable error, but not too easy to check it unless you have the equipment. Nev

 

 

[Sapphire]

Of course, Metalman, after all the discussion you meant that you wrap your lips around the pitot tube and apply suitable pressure as observed by someone in the cockpit watching the asi. There is no terminology for that technique that I can google under "aviation terms" Just use your terminology and tell them you're *Metalman*, able to leap from tall buildings in a single bound. That should stop any uncomfortable queries.

 

 

[Ballpoint 246niner]

20 yrs no ASi- 2000 hrs, fly the attitude and listen to airflow( not the radio!!), feel the wing.

 

T-shirt reads "Anal about Airspeed". !!

 

Bloody instruments!!!!!

 

 

[facthunter]

A piece of wool will do it, but not with the Concorde. Nev

 

 

[Tomo]

I got a hole in the top of my canopy which I stick my finger out after licking it. If the front of my finger gets' cold I know I have airspeed...

 

 

[facthunter]

From now on there will be hundreds of holes in the canopies of U/L's as the multitudes follow in the path of their idol, slavishly seeking to emulate his every move. You've started something now Tomo. nev

 

 

[Ballpoint 246niner]

I got a hole in the top of my canopy which I stick my finger out after licking it. If the front of my finger gets' cold I know I have airspeed...

Do you check the spit/ cold values before takeoff mate-better -it's coming out in an AIP soon....!

 

 

[Sapphire]

Ive never had a plane with a hole in the top of the canopy, but sometimes there is a drain hole in the floor. A wet "appendage" would work just as well there

 

 

[Bryon]

Ive never had a plane with a hole in the top of the canopy, but sometimes there is a drain hole in the floor. A wet "appendage" would work just as well there

If you think I am hanging my "appendage" out in the airstream, my wife has some words for you........

 

 

[Sapphire]

It could be a cheap alternative to viagra if the wind chill factor was bout -20c

 

 

[facthunter]

If you fly high it might be like the eskimo who was engaged to the model, she broke it off. Nev

 

 

[Sapphire]

Don't forget to retract before landing or you will leave abrasion marks all the way down the runway! [time for another preflight...]

 

 

[facthunter]

that probably qualifies as retractable gear. Nev

 

 

[ExJourno]

Did the daily on a Lightwing GR 912T on Friday. Didn't find anything during the daily/preflight... but what I found when shutting down gave me a chill.

 

Mag 1 off. No problem. Engine settled. Mag 2 off... let's try that again, Mag 2 on and off... engine still running. A bit more force on the Mag 2 switch lever, engine starts to shut down, release pressure engine stays on... force the switched down engine dies. A short somewhere, clearly. During the pre-takeoff sequence the mag switches had both seen about 100 or so RPM drop when turned off. But is was still chilling to have one switch fail on shutdown. You can swing start a Rotax 912, can't you?

 

I'm calling it a coincidence that after checking the mag switches were both off during the daily, I couldn't stop wondering how badly I'd mangle my hands if the engine fired while I was rotating the prop to get the oil to burp/gurgle. Until friday I hadn't given it a thought.

 

 

[facthunter]

It is a risk (if the switch doesn't earth. True. When you are rotating the engine to get the oil back into the tank it should be rotated fairly slowly to allow some blowby past the rings. That is what scavenges the engine . There is no scavenge pump. Nev

 

 

[Sapphire]

Spent two years hand propping a plane. A hot engine can fire with mags off as if it was a diesel. Hope my next plane has a starter

 

 

[facthunter]

Purging the oil back to the tank is not required if the engine hasn't been sitting for a while, on a 912....Treat all props as "live". Play it safe Nev

 

 

[eightyknots]

Did the daily on a Lightwing GR 912T on Friday. Didn't find anything during the daily/preflight... but what I found when shutting down gave me a chill.Mag 1 off. No problem. Engine settled. Mag 2 off... let's try that again, Mag 2 on and off... engine still running. A bit more force on the Mag 2 switch lever, engine starts to shut down, release pressure engine stays on... force the switched down engine dies. A short somewhere, clearly. During the pre-takeoff sequence the mag switches had both seen about 100 or so RPM drop when turned off. But is was still chilling to have one switch fail on shutdown. You can swing start a Rotax 912, can't you?

 

I'm calling it a coincidence that after checking the mag switches were both off during the daily, I couldn't stop wondering how badly I'd mangle my hands if the engine fired while I was rotating the prop to get the oil to burp/gurgle. Until friday I hadn't given it a thought.

No doubt about it, it's a worrying thought which hadn't occurred to me either.

 

 

[Tomo]

It takes a fair swing to start a Rotax, but ALWAYS treat a prop as live, even if it's on a Jab...

 

 

[turboplanner]

Spent two years hand propping a plane. A hot engine can fire with mags off as if it was a diesel. Hope my next plane has a starter

I've had a few that were hard to start, but never had to prop one for two years!

 

 

[Guernsey]

It takes a fair swing to start a Rotax, but ALWAYS treat a prop as live, even if it's on a Jab...

I totaly agree, I have a wooden prop from my old Drifter which is hanging up high on the wall in the lounge but when I help with the housework I never feather dust the prop.... it could fall on my head and kill me.

 

Alan.

 

 

[Sapphire]

The last time I refuelled my a/c I sighted the level and checked for water contamination which was removed.. We assume that what is left in the tanks is all suitable fuel, but it may not be. Other contamination and fuel quality arn't always discovered in normal pre-flight checks. I talked to another pilot about that. He mentioned that during refuelling a large bee or fly entered his fuel tank and never came back out. Some time later he had fuel flow problems.

 

Fuel lines are only about a quarter inch in dia. and an inline filter would be even smaller. One of those over fed flies can turn your engine off as fast as a selector turned to off. I avoid this by never leaving my cap off unattended ie refuelling from petrol containers. Everybody knows that old fuel is no good, especially if mixed with two stroke oil. Part of the preflight for me is to remove old fuel and put in my car to mix with good fuel there. Two stroke oil put into fuel lowers it's octane rating so buy high octane fuel and use within a month. Also old fuel eventually turns to a varnish and coats the inside of your fuel system. Other contamination exists. I once filtered the fuel I drained from an a/c and found lots of small black flakes, something that could even block a fuel filter. Who knows what the previous owner stuffed into his tank.