Friday, 20 July 2012

A base for a week

One hour drive from home to the nearest airport and another two commuting flights later, I make it to my assigned base for the next few days.
After checking-in at the hotel, a walk in the city centre reveals what looks like the perfect place to enjoy your summer holidays.
No doubt, this is going to be a nice week. I'm on earlies, which leaves me with a lot of spare time in the afternoon.

Day ON 1, 3:20 am, time to get up.
The hotel's jacuzzy would have been much appreciated as a way to wake up but it isn't available up until 9 in the morning.
4:40 am, all the crew meet and the Captain introduces me to the four flight attendants. We review the weather reports, flight plans, notams, airfield charts and fuel calculations.
Time comes to decide who will be flying which leg. I was expecting to be PM (Pilot Monitoring, in charge of the walkaround, radio communications, paperwork, FMC inputs, ..) on the first sector and flying us back home as our destinaton airport uses a narrow (30m / 98ft) runway.
The Captain, in fact an experienced and well rounded LTC (Line Training Captain) gives me the opportunity to do the landing there.

Three hours later and established on final with Flaps 5, I disconnect the Autopilot and Autothrottle as we break through the low level stratus.
The first glance outside immediately makes me feel way too high from where we should be (standard 3° glide path) but this in fact is all down to the optical illusion from the runway's non-standard width. Eyes inside to follow the flight directors and maintain the speed, eyes outside to follow the PAPI's (4 lights on the side of the runway to insure a correct descent angle) and down we go.

'100', '50', '40', '30' gentle back pressure on the yoke, '20' throttles back to idle, '10', touchdown.
'Speedbrakes Up', both reverses to the 2nd detent, 75% N1, 100 knots, 80 knots, idle reverse, 60 knots, override of the autobrake and the Captain takes over control to vacate on the taxiway.
None a glassy smooth landing but enjoyable nonetheless.

By 1pm, we're back home and the paperwork filled-in, I catch a bus to the city centre. Unfortunately, none of today's Flight Attendants are up for a meet-up in town tonight.
After a quick stop at the hotel, it's time for a city tour ... (see photos below).

Day ON 2. Wake-up at 6 am which, on earlies, is surprisingly late.
After an eventless flight into Scandinavia, we're on the ground getting the aircraft ready for the flight back home.
With a temperature of 17°C and a fair headwind, you would normally expect no issue regarding take-off performances. Calculating the Vspeeds (V1, Vr and V2) and take-off thrust setting, you start with lower fixed derates (22K, 24K, ..) and reduce it then further by applying an 'Assumed temperature' (equivalent to Flex on Airbus), depending on the runway length available, climb gradient required, temperature, airport elevation, QNH, wind, and of course aircraft take-off weight.
Now with a rather short runway, 180 passengers, 120 bags and 13 tonnes of fuel, we might indeed be very tight.
We skip the 22K calculations and give it a go with 24K but clearly it won't do it.
With 26K and no assumed temperature (full thrust), we can take-off at 70.0 tonnes on those given conditions.
Today however, our aircraft will weight 70.4 tonnes on take-off (assuming a 150kg fuel burn off during taxi).

Now there's a way to get an extra margin if needed and this is called a Bleeds Off take-off, something we very rarely get a chance to do. 
The bleed air taken from the engines pressurizes the aircraft as soon as the take-off thrust is applied (still on the ground), taking a little bit of thrust off the engines during the take-off roll, which in turns reduces the performances. If we do a Bleeds Off take-off, no more bleed air is taken from the engine and the APU (Auxiliary Power Unit) takes over and supplies it up to 17,000 ft.
Checking the performances again, we're now able for a take-off at 70.55 tonnes.

20 minutes later, aligned on the runway and cleared for take-off, we set 70% N1 thrust on the brakes, release them and here comes the maximum thrust. Airspeed increases quickly but what's more noticeable is the closing speed with the runway's end. '80 knots' call, quick look at my PFD and answer 'check'.
I can see we're now reaching 100 knots, the aircraft does feel very heavy. 120 knots, still another 26 to be able to get airborne. We're now in the touchdown markers (yellow blocks on the runway in Nordic countries) of the other end. 'V1' ...... 'Rotate!'. 146 knots as I pull the yoke and lift us off the ground. The main landing gear passes a few feet above the runway's threshold and the mighty pocket rocket starts its 4 hour journey to warmer lands.
Passing 4000 feet, the Captain completes the After take-off checklist specifically adapted for Bleeds Off departures. The main point being to replace the APU bleed air with engine bleed air and then switch off the APU.

8:00 pm, a beer in the hand and a dozen FA and pilots to share it with, a great way to end the day.