up the answers to your navigation problems, including polar grid
navigation, pressure pattern flying, crosswind components, and
wind solutions. These computers automatically compensate for
the temperature and compressibility factors found at high speeds.
Tough laminated plastic, with carrying case.
PROS: - Good quality material, - clearly marked, - no sloppiness in the bushing/discs, - carrying pouch.
CONS: - Several markings are very SMALL (i.e., True Air Speed and Density Alt. at left of computer hub, Pressure Alt. at right of computer hub, minutes/seconds on the Time circle - 5:00, 16:00, etc.), - No manual, although the images advertise a user manual (there is, however, a link listed on the cover, where the user can download a pdf file), - The edges of circles and cursor are not finished (deburred) , so circular scratches will appear on the computer after several rotations. - MOST IMPORTANT: The user will find out that on this computer 10 x 2 = 19.5, 15 x 2 = 29.5 instead of 30, and so on. When a user aligns the unit index (black 10), the Time index and some gradations are correctly aligned, but half of markings are not. That gives a sizable error for many calculations. The difference between 2950 and 3000 lbs. of fuel may be the difference between landing at destination or in a corn field. Or not be able to take off in a warm day. I returned it after checking other units. Either this was a bad batch, or Jeppesen has a crappy QA. It's a shame for a company of its caliber (Boeing). The replacement, CR-6 from APR Industries has markings as they should be: big, clear, and aligned correctly. (Disclosure: I don't make a pitch for APR. Their choice of materials is crappy Jepp is better in this area. And you can see through the yellow mask.)