To flights on devices concern the flights ночью: At equipment by aircraft devices for such flights it is necessary to know and take into account some moments. It is necessary to care of reliability of instrumental equipment. Reliability is provided by off-line operation of each device. Devices, whenever possible, should be mutually duplicated directly or indirectly and also have independent power supplies. For example: gyrohorizon is indirectly duplicated by electronic turn indicator and variometer. Speed indicator – by gyrohorizon, variometer and attack angle indicator. Altimeter – by radio altimeter or GPS or reserve altimeter. It may seem to be a reassurance, but such illusion can arise in warm apartment, at the computer. In flight, when you will dangle in clouds and chances of your life prolongation will directly depend on reliability of the devices, an idea on reassurance will not seem absurd. Electronic aviation instruments, which have doubtless advantages before mechanics ones, have recently appeared. These advantages are brightly and convincingly described by numerous manufacturers and sellers. However, they also have disadvantages, which are not detected by anything, but which should be taken into account. There are separate devices and complexes, which display all aviation instruments on one monitor. Separate devices as a matter of fact copy mechanical ones, only by use of tiny detectors and microelectronics their weight and cost price (do not confuse with the price) were considerably decreased. They work perfectly and possess higher accuracy, but have 2 small traits-minuses. Indicators on such devices are LCD (liquid crystals) as a rule, and at temperature of +5 degrees centigrade they start to work lazily, and at temperature of -10 degrees centigrade they almost freeze. Besides they let polarized light pass, it is actual for those, who uses sunglasses of the firm "POLAROID". Pilots like these glasses as they protect from fulguration on sun and from bright light of clouds very well. If to slightly bend head in such glasses to the right, the image on indicator will disappear, and it becomes black (you can check it on monitor of your PC). The second minus is that power supply is required, though this problem is solved easily. Flight complexes include the block of detectors and processings of signals and big color LCD monitor, which is set on control panel and graphically represents all necessary data. Externally it looks very beautiful, moreover it also works fine. Such devices are especially admired by amateurs of computer airsimulators. They represent rapid scientific and technical progress, carrying away to unknown galaxies. Manufacturers accentuate attention on that the whole complex is actually one small box. Cabins of liners and fighting monsters with the same graphic indicators appear inwardly. However, we shall try to find small spiteful minuses. In liners and fighters there also are monitors, only not LCDs, but EBTs (electronic beam tubes), which luminescence brightness is higher in times, and nevertheless the problem of "black" is not solved yet. At illumination by bright sunlight reading from indicator is difficult, therefore they are closed, whenever possible, by different shields and it is recommended to wear dark clothes to lower fulguration. Except for that LCD monitors cannot work at low temperatures and are sensitive to vibration. There also are boxes in liners and fighters, only all them, taken together, will hardly get into a box from the TV. Among these boxes there will be both mechanical vertical gyroscopes, laser gyroscopes, inertial platforms and induction detectors, and all this in 2х - 3х copies to increase a reliability. Because of offered complexes are unary device, reliability suffers, as in case of a fault there is a big risk to remain without devices – without all devices. Therefore, if flights on devices in really bad weather conditions are assumed, it is desirable to supplement the complex with separate devices, as in usually done on liners and fighting monsters. It is desirable to show 2 examples, illustrating foresaid: in 2005 in Gromov LII similar complex of one foreign manufacturer went into test. It was set aboard the plane SU-27. In a day of the flight there was 10-balls overcast with the bottom edge of 400-600 m. The flight was carried out by our well-known experienced test-pilot. After rise at task execution there was a refusal of the complex, test-pilot could hardly fly out of a cloud, plane-leader flied, SU-27 opened the way in clouds in compact column and landed. After landing during approximately 3 hours in very convincing speech of a pilot from literary words there occasionally were preposition, pronouns and conjunctions. A case from own experience. Plane SU-24 in 1990. Night , low cold ceiling. On rise after rotation during switch in climb at pitch of about 20 degrees there was a refusal of the gyrohorizon. It was detected by strange reaction to the handle. Keeping the plane from a list by the device DA - 200 (combination of angular-rate indicator and variometer) it was possible to switch the plane in horizontal flight, switch off the afterburnings and turn to reserve attitude heading reference system. At equipping aircrafts for flights by devices try to provide yourself with flight information for any variants of refusals of power, warmed cabins, refusal of illumination. Spent for it forces and means can save your life.