Round the World Flight Daily Journal: Night Falls in Abu Dhabi

Wish you could be here with Adam and me, as the night falls over Abu Dhabi. Nothing, no moment, could better capture the exquisite pleasure of this journey – and the relentless thought that it requires. We were each awake at five this morning, a cup of coffee and a quick shower, and in a taxi to the airport, OJAM, the Amann Civil Airport at Marka, by 0700, to arrive by 0730 local time and depart by 0800 for the long flight across Saudi Arabia, Bahrain, Qatar and to Abu Dhabi in the U.A.E.

We are now, as I write this, on the top floor terrace of our hotel revisiting our flight planning for today’s six-plus hour flight, making some corrections, analyzing where it worked and where it didn’t and congratulating ourselves a bit for flying more than a thousand nautical miles across Saudi Arabia and landing within minutes of our flight planned time and – much more important – consuming almost exactly the number of gallons we estimated. We, principally Adam, flight planned at FL190 for 105 gallons. Our climb rate was significantly less than we had hoped, the product of a hot and heavy departure, to the extent that we had to ask for dispensation from the climb requirements of the SID out of OJAM, which was granted by the tower with no complaint, as in, “Fly runway heading expect vectors.” Departing runway 24 into the hills of Amann, a city of hills, gave us pause, even as we discussed it the night before but we noted the provision for an alternate climb in the SID instructions and found an obstacle chart buried in the Jeppesen charts and so satisfied ourselves that we would almost certainly have options. But our cruise numbers were – intentionally – pessimistic, that is to say conservative, and therefore compensated almost exactly for the additional fuel and time burned in our climb to FL190. We had calculated a TAS (true airspeed) of 170 and a ground speed of 200 knots at cruise, but we had also allowed the usual 16.x GPH to achieve those numbers and, since at FL190 we were above the critical altitude of the turbo-normalized engine system, we could make only 2300 rpm and less than the usual 23 inches MP and so burned only 15.x per hour – and still we made the 170 TAS and 200 GS we had estimated. We made the TAS because of the altitude and we made the 200 knot ground speed because the 30-knot tailwind component at that altitude appeared as forecast. We had about 30 knots of tailwind for most of the flight just as predicted. So we calculated the time based on the winds, but we calculated the fuel based on no wind, just in case. So, bottom line, we flew more than six hours, more than 1050 NM over Saudi Arabia and Bahrain and Qatar and nailed the fuel burn and the time to within less than one percent of our calculations.

So here we are, recalculating, reliving, re-analyzing and adjusting our methodology for the long legs to come, which is difficult and involves math, something Adam and I both love, but something that comes hard after a day such as this. For now, we are enjoying the warm breeze on the rooftop terrace, enjoying the pilot talk as we break down our calculations from last night and their result today. Don’t do this sort of thing unless you really enjoy the minutiae of flight planning and the mysteries of power curves. There will be times when the consequences of those obscure charts that you never quite understood will loom large. We had such a day today. But here we are sitting high up above the capital of the United Arab Emirates, having a beer as the sun sets and the temperature moderates and enjoying the warm wind and the lights of Al Bateen Airport and the great mosque, the minarets of which protrude into the flight path of runway 31 and which we sailed by this afternoon on the ILS runway 31 approach and are now lit by strobes to warn pilots landing at night. These are the hugely gratifying moments and are particularly so when the wind is warm, the beer is cold, and the city lights twinkle in the fading light.

Nevertheless, we made a mistake on the fueling that we need to think about seriously. More about that later.