Pig wrote:
I’m always perplexed why the initial taxi clearance is to C1 and not B1, especially having built that lovely new taxi way. 1000m TORA from C1 for 19 is fine for an SR22, but I always ask for, and go for 1383 from B1. Why wouldn’t you, and why would tower let you leave all that lovely runway behind you ? I’m sure there is a reason, but I can’t think of it from a pilot’s perspective.
Occupancy. They want to spend as few time as possible with you, so from Apron to nearest acceptable runway and then would you bu**er off please. At many airports that is what it appears like to me. If you taxi to the beginning, you take longer to get out of his hair.
My reaction is like yours usually, unless I can see a reason too and the lenght left behind me is not too long. Happened to me at SZG a few times but it was clear why as an airliner was before me but would not be able to depart before us, so they let us out before him.
Intersection takeoffs, or not can be driven to excess for our small SEP toys… say you’re taking off from LFSB from runway 15, will you insist on using the whole length, just short of 4km, for every take-off?
Talking airliner jet ops, one things which exacerbates risks during intersection departures, is the practice of reduced takeoff thrust. The vast majority of takeoffs on Boeings, Airbuses, and haveyounots, are performed using flex values, the benefit being reduced engine maintenance.
Now when the needs for a full thrust (TOGA or whatever it’s called) is required, this will show in the calculations, assuming the correct data is entered. Some places, thinking LGMK Mikonos with a fully loaded A320 will guarantee full rated power, and appropriate flaps settings.
There have been many instance when both, full thrust and flaps settings have been calculated, briefed, confirmed, and still not properly set at the initiation of the TO roll. The causes? Usually two fold, distraction and complacency… humans at work.
One way to mitigate the risk was to place either the QRH binder in front of, or the plastic checklist between them thrust levers for a last verification prior to action.
Dan wrote:
Intersection takeoffs, or not can be driven to excess for our small SEP toys… say you’re taking off from LFSB from runway 15, will you insist on using the whole length, just short of 4km, for every take-off?
Given that in BSL you usually get the short runway anyway not necessarily. The even better example is Geneva, where, coming from the GAC, you usually get an intersection right in the middle of a 4km runway. In most cases, that is absolutely ok.
I’d take several things into account, in nor particular order:
- Traffic: If there is no traffic whatsoever, I might opt for a longer take off distance available than originally offered. In the case of Salzburg, I was taxiing all alone down the parallel TWY and was originally sent to an intersection some 1/3rd down the runway for take off. I then asked if full lenght was convenient and they said sure, so I took it. If on the other hand I can see that they are trying to shoehorn me into a busy traffic flow, I’ll try to accomodate as much as possible, however with particular regards to Wake Turbulence.
- Wake Turbulence: If I need to take off from a runway where there is a string of airliner arrivals before my departure, taking off from an intersection past the touchdown point may be quite an intelligent thing to do. If on the other hand you are going behind a bunch of departures, I’d prefer to start the take off so that I am airborne and stay over or out of the climb path of the airliners, to avoid their wakes.
- Reland possibilities and climb out path: If the area past and beside a runway is built up and would leave few landing spots in case of that EFATO at 200 ft, I would try to get as much runway as possible in order to be able to land straight on the remaining runway. Same considerations for the climb out path. If it’s full of obstacles, I prefer to use more runway in order to be higher at the end.
And obviously performance.
It’s hugely dependent on the situation. But I would not shy away if there are factors which make it the better soution to ask for more TODA than originally offered.
