TM  1-1520-240-10 9-1-24            9-1-54.  FUEL LOW and FUEL PRESS Cautions. If  the  FUEL  LOW  and  FUEL  PRESS  cautions  come  on perform the following: WARNING Failure of main tank fuel boost pumps with the crossfeed open and a fuel low condi- tion may result in a dual engine flameout. Nose low attitude should be avoided. 1.   XFEED — CLOSED. 2.   Land as soon as possible. 9-1-55.  Electrical System. 9-1-56.  NO. 1 or NO. 2 GEN OFF Caution. NOTE If either an AC or DC system fails with no bus tie, the hydraulic oil cooler fans will not func- tion. If any other system caution comes on or a system is lost, a bus tie does not exist. The primary caution segment lights to look for in determining whether or not a bus tie exists are L and R FUEL PRESS NO. 1 and NO. 2 RECT OFF, and NO. 1 and NO. 2 AFCS OFF. If no bus tie exists and the failed generator cannot be restored: Land as soon as possible. If only the NO. 1 or NO. 2 GEN OFF caution is illuminated, a bus tie exists. 1.   GEN switch — OFF RESET, then ON. If the caution remains on: 2.   GEN switch — OFF. 3.   Land as soon as practible. 9-1-57.  NO. 1 and NO. 2 GEN OFF Cautions. Should both generators fail, both transformer-rectifiers will also be disabled. This condition will be indicated by loss of both AFCS (which can result in abrupt attitude changes) the lighting of both AFCS, OFF, GEN OFF, and RECT OFF caution. Since there will be a loss all primary attitude,  instrument,  navigation  and  stabilization  sys- tems, the primary concern is to land as soon as possible and the secondary concern is to restore electrical power. The  only  electrical  power  available  will  be  24-volt  DC from the battery. CAUTION If both generators fail, the main tank boost pumps will be inoperative. If flight is con- ducted above 6,000 feet PA, descend be- low 6,000 feet PA as soon as possible to avoid a dual engine flameout. If applicable, reduce  airspeed  to  100  KIAS  or  Vne, whichever is slower. ⁷¹²   Also all normal beep  trim  functions  will  be  inoperative. The control of engine RPM will be accom- plished via the EMER ENG TRIM 1 and 2 switches.  LCT  and  DASH  actuators  will remain  programmed  at  the  airspeed  at which the generators failed. 1.   Land as soon as possible. 2. 712 EMER ENG Trim — Adjust. If unable to land proceed as follows: 1.   Airspeed — below 100 KIAS. 2.   Altitude — below 6,000 feet PA. 3.   AFCS — OFF. 4.   PDPs  —  Check  circuit  breakers  and  place gang bars down. 5.   Each GEN switch — OFF RESET, then ON. Electrical power is restored (from either generator): Land as soon as possible Electrical power is not restored. 1.   APU — Start. 2.   APU GEN — ON. 3.   Land as soon as possible. 9-1-58.  No. 1 or No. 2 RECT OFF Caution. NOTE If a DC bus-tie does not occur (No. 2 Rect Off), power  to  open  the  cargo  hooks  in  normal mode is not available and the associated hy- draulic cooler fan will not function. Other cau- tions will be on, such as L FUEL PRESS (if crossfeed valves are closed). DC bus tie has not occurred: Land as soon as possible. DC bus tie has occurred (only the RECT OFF caution will be on): 1.   PDP’s —Check. 2.   Land as soon as practicable.