BackTracking
 

Hey, I have a question about backtracking.
I had a flying lesson on friday to see how it is, and i'm starting training in december hopefully for my GFPT and PPL and possibly CPL, I was just wondering, when we took off, we were in a Cessna C172SP, and the runway had about 50 metres to the threshold from the closest taxiway. like

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so anyway, i noticed that my instructor backtracked, though we took less than a 3rd of the runway to take off, why is this? is it mandatory to backtrack?

(I was at YRED by the way, if it helps)

It was weird, made it fun, but the lesson went really great :)

PyroTek

There is a common saying in aviation that says runway behind you is about as useless as air in the fuel tanks when the fan stops.

Am I meant to interpret that as "this is whats called the height of safety to backtrack"?

PyroTek

I’m not familiar with that term but put simply by using the full length of the runway in a lighty, if the engine stops you will have a greater chance of stopping on the runway or landing straight ahead on the remaining runway. Of course this will all depend on the length of the runway in the first place. Another point is by using the full length of the runway your obstacle clearance during your initial climb out will be greater.

Pyrotek,

Unless there is another reason not to, it's always best to use every scrap of runway at your disposal. When there's only a short 50 metre taxi to go it's worth doing it. Every now and then someone comes a cropper because they usually depart from an intersection and on one day they forget they are at max weight and it's 37 degrees.

Walrus

Was doing a Chief Pilot check flight from YRED a few moons ago when a C210 decided to sneak in front of us and try to get away from the middle intersection on 07. Didn't quite fit so we had to go around and his mains got awfully close to touching grass at the far end of the runway. On top of that he decided to head stright off into some rather non VFR looking weather........all of which was very interesting to the CASA field officer sitting to my right.......

Just another reason to backtrack.

If it was 07 you were using i would most certainly backtrack for every inch available, not too many options there for the first few hundred feet after take off.

yeah it was 07 in use, thanks for the info, so it is a safety precaution as i thought :).

And it's good airmanship as well to use all available runway. Good luck in your training and enjoy!

PyroTek,
Have to admit, I have been guilty of the occasional intersection departure where the TORA from that point was more than adequate for a PA28 /C172 type.

I remember one occasion though taking off in a C210 full fuel and pax and during the takeoff roll saw that the ASI was still on zero with my speed probably around 60kts. Took me the remaining length of to bring the thing to a comfortable stop. That little incident changed my attitude on intersection departures for good. If that was tried using a short field technique from an intersection using less than the available full lenght, I probably would have had to make a quick decision and possibly elected to continue and fly the damn thing around the circuit without the ASI which I imagine would not be much fun. Thankfully I didn't have to do that.

An airport where I work in the Pilbara has a rwy over 2000m with the taxiway to the apron exactly half way along. Very very few pilots, regardless of acft type do an intersection departure. Except rotor heads :}

Try asking for a backtrack in a lightie on Rwy 15 at YBCS - you'll get an interesting response from the Twr.

Dr :8

"..... and possibly elected to continue and fly the damn thing around the circuit without the ASI which I imagine would not be much fun."

Why?

Power + Attitude = Performance

This should get you safely around the circuit in most GA aircraft.

The last time I had to deal with no ASI was in my first flight in an A36. On T/Off the ASI came up to 70 kts - and stayed there for the entire circuit.

Personally, I think that demonstrating the ability to successfully fly a circuit without ASI should be a requirement for a PPL (or whatever its called these days).

Dr :8

Fork:
is it just straight "no"?
or would they make the lighties cross the runway to get to B2, to half the backtrack?

ForkTailedDrKiller

Unless things have changed significantly since I flew from there about seven years ago, I use to do it on a regular basis when heavy, which was most of the time. Requesting B2 on taxi and depending on the time of the day would dictate how I got there, i.e. whether I would backtrack from A2 or cross the runway at A2 to B3 then B to the holding point B2. Common sense though would tell you that in a light single/twin, 1800m from A2 should be enough under most conditions, after all full length is 3196m.

PyroTek

As above.:ok:

Pyro,

If and when you start training and find yourself at a controlled airport all you need do is say "require full length" or "require backtrack".

Don't request it if you really require it, particularly in performance-limiting situations. "Request" gives ATC discretion whereas "require" does not. Having said that, I don't know of anyone in ATC that wouldn't grant your request (with the exception of location-specific procedures, if there are any).

Your instructor should explain all this to you when the time comes.

I.J., I know of one particular gent who taxied out at Leinster in a Cherokee, turned 180 degrees when he got to the runway and blasted off on the taxiway.

Apparently it was the most into-wind taxiway!:eek:

The WMC airport manager was really impressed.:ooh:

I've found myself backtracking from A2 at YBCS for RWY15 in a lightie, usually an option due to wake turbulence or spacing not an operational requirement.

404 Titan

Still the same nowadays. They just send you to the other side if it's busy.

At 853m YRED isn't a long strip. You would be surprised how far it is from the taxiway back to the threshold, Pyro. You would be looking at closer to 90m than 50:ok:

What 404Titan says, it could be all the difference stopping short of the levy bank or crunching into it. After the levybank nature will give you a helping hand in pulling up:}

speaking of buggered ASI, had an interesting one in an Arrow, accelerated down the strip, asi working well, 70 kts rotate, climb at 80, then 90 then 110 then 140 then 180, the ASi kept on winding up! well past redline then back around for another lap. the needle then came back to 200kts then to the stop, then back to 80 kts, then back to the stop, one busy and confused Bug going for a walk along the Pitot system. completed a circuit and touchdown at 170 kts! what this has to do with intersection departures umm, i dont know.

yeah, 50 metres was a very rough estimate. ah well...

However, at the end of the day, YOU are Pilot in Command of your aircraft and if you want the runway, use the runway. (You may just have to wait a bit).

As someone has quoted, runway behind you is as useful as fuel in the bowser or altitute above you. ;)