B747-400
Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Fatigue; Physiological - Other
Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Illness / Injury; Ground Event / Encounter Other / Unknown
General Flight Cancelled / Delayed
Weather; Company Policy; Aircraft; Human Factors
For some unfathomable reason the flight out of the desert near [city] was scheduled for [mid-day] local during the summer. When we arrived at the aircraft an hour and a half prior to scheduled departure; Maintenance advised the aircraft was ready to go. I climbed upstairs to the flight deck to find the temperature was 110 Fahrenheit with no APU or pack on; every light on bright and no foil shades installed. I immediately started the APU and packs then proceeded to install the foil shades. Since all the avionics were already powered up I was not surprised to see numerous anomalous indications. As Maintenance tried to deal with those indications the present leg faults in the CMC (Central Maintenance Computer) ran to 13 pages.After over an hour working with Maintenance to clear the anomalies I had managed to lower the temperature on the flight deck to 99 Fahrenheit. One outstanding avionics issue remained after an hour and a half that the datalink was not working. Maintenance Control made the decision to not defer the datalink and have maintenance continue to troubleshoot the problem. While I was able to take a couple of breaks after that in the maintenance office; my presence was required often on the flight deck to answer maintenance questions about the proper operation of the equipment. By the time Maintenance signed off on the airplane and we were able to launch it was 6 hours after we had reported to the airplane. In addition to the huge heat stress we had been exposed to humidity that was down to 4 percent.During the flight I experienced a pounding headache; fatigue and a loss of concentration and appetite which are all signs of heat exhaustion. The condition I was in on arrival led to having to call fatigued so I could enter rest instead of a further two and a half hour limo ride to ZZZ2 that scheduling insisted on.This incident shows that a lack of unity of command or coordination leads to a failed form of operational control. Apparently the departure time in ZZZ is driven by the decision to arrive three hours prior to departure in ZZZ1 in order to save parking fees or whatever departure driven reason. That departure time ignores the reality of desert operations where the aircraft originated. In the desert departures near first light or after dusk at suitably equipped airports are much better for performance reasons; both human and equipment. No effort of coordinating the departure seems to have been made between sales and maintenance plus no pilot appears to have been involved with the scheduling.Additionally ZZZ is a Captain only airport with less than 7;000 ft. of runway that is uncontrolled and requires clearances by phone. While I personally have experience in both desert operations and maintenance test flights randomly assigning crews to maintenance ferry flights is frankly insane. This type of operation is not trained at this company in any initial; transition or recurrent course. If there is not going to be training for this type of operation to all pilots a separate cadre should be selected and trained for these kind of flights.I suggest the following to avoid this happening again:All departures from non-routine locations or substantial maintenance events have to be coordinated with the local maintenance representative and flight operations in addition to any other departments such as sales.For all non-normal airport [and] maintenance operations a trained cadre of pilots be used exclusively.
B747 Captain reported extended maintenance delay and extreme heat prior to departure leading to exhaustion and a fatigue call.