§3.184 to indicate that the design speeds.

are stated in terms of equivalent airspeed, EAS which is already defined in § 3.1(d), and in miles per hour. The amendments to §§ 3.183, 3.184, 3.186, 3.187, 3.188, 3.190, 3.195, 3.197, 3.198, 3.199, 3.217, 3.217~1, 3.220, and 3.270, which were proposed to make the strength requirements appropriate to the speed, altitude, and maneuverability characteristics of small turbine-powered airplanes, have been deferred for further study. The present requirements on factors of safety and inspections for structural castings specify a special factor of 2.0 for visual inspection only, and a factor of 1.25 when radiographic inspection and strength tests of 3 sample castings are employed. Section 3.304 as adopted herein provides for a series of casting factors, and corresponding test and inspection requirements, which reflect current methods and practices. A minor revision in the format of the regulation as proposed has also been made and a new paragraph (d) has been added for purposes of clarification. In addition, May 3, 1962 March 27, 1962 Effective: Issued: the amendment now provides for alter~ native methods of compliance with the requirements therein. Section 3.304-1 has been deleted since its provisions have been incorporated into § 3.304, Section 3.357 currently requires an auxiliary means of extending the landing. gear be provided if other than manual power is used. This provision is un- ” necessary in the case of amphibian airplanes, since service experience has shown that such airplanes can be landed safely, on land or water, with the landing gear retracted. Therefore, this section is amended to exclude amphibian airplanes. Section 3.359 currently provides that the aural warning device function continuously after the throttle is closed until the landing gear is down and locked. To remove the ambiguity which arises in the case of muitiengine airplanes, this section is amended to specify that the warning occur and continue when one or more throttles are closed. In this connection, §§ 3.359-1, 3.359-2, and 3.359-3 are being deleted and the acceptable means of compliance set forth therein are being incorporated in a note. The increasing use of tinted windshields to reduce sun glare has raised questions as to the possible adverse effects on pilot vision during operations under poor lighting conditions. On the pasis of automotive experience, § 3.383 is peing amended to require that windshields and windows forward of the pilot’s back have a luminous transmittance value of not less than 70 percent. This value of transmittance will permit consideration of thick material in the windshield if it should be needed for structural reasons or if bird-proof windshields are used. Sections 3.390(d) and 3.715 presently require an additional factor of safety of 1.33 on the loads for seat and safety belt attachments, amd § 3.306 requires a fac~ tor of 1.15 for structural fittings (attachments). Sections 3.390(d) and 3.715 are being clarified by inserting a statement that the 1.33 factor may be applied in lieu of the 2.15 factor, not added to it. This is consistent with the general principle that only the highest factor intended for a similar purpose need be applied. However, if castings are used, the casting factor specified in § 3.304 would still apply, since this factor is intended for another purpose. Section 3.432 restricts the routing of pressure crossfeed fuel lines unless means are provided to permit flight personnel to shut off the supply of fuel to these lines, or unless any joints, fittings, or other possible sources of leakage installed in such lines are enclosed in a fuel- and iume-proof enclosure ventilated and drained to the exterior of the airplane. Experience has shown that pressure crossfeed lines do not require provi-~ sions different from other pressure fuel lines. Accordingly, this section is being deleted. Section 3.581 requires that powerplant cooling provisions be capable of maintaining component and fluid temperatures at or below the maximum established limits under critical conditions of ground and flight operation. Since modern airplanes have minimum as well as maximum limits, § 3.581 is being amended to require that cooling provisions be capable of maintaining temperatures within limits. For the same reason, the word “maximum” is being deleted from § 3.582. Sections 3.586 and 3.587 establish cooling test procedures for single-engine and multiengine airplanes. Section 3.587 provides that the airplane be in the configuration specified in § 3.85, which covers climb performance, while § 3.586-is silent in this respect. Section 3.85, however, provides that the cowl flap setting, which is part of the airplane configuration, be that employed in the cooling test. Yo avoid ambiguity it is being specified that the applicant select the cowl flap setting to be usec in establishing cooling system capability. Several amendments to §§ 3.681 through 3.693, concerning electrical systems and equipment are being made. In particular, § 3.682 now deals with electric power sources, and revisions are being made to 8§ 3.688, 3.690, 3.691, and 3.693 which cover master switch arrangement, protective devices, and electric cables, respectively. In conjunction with these changes, §§3.681(b), 3.681-1, 3.681~2, 3.682-1, 3.688-1, 3.688-2, 3.690-1, 3.690-2, and 3,693-1 are being deleted because the material contained in these sections is being included, or already is included, in other sections. ‘Two changes are being made to the lighting requirements. Figure 3-16 now specifies that position light intensity for angles 40° to 90° above or below the horizontal be at least 2 candles. Because this results in an irrational discontinuity when related to the other data in Figure 3-16, Figure 3-16 is being amended to require an intensity of 0.05 7 for these angles. The current anticollision Ught requirements in § 3.705 permit 0.03 stera~ dians blockage in the rearward direction. In view of recent qualitative studies it has been determined that such a limita~ tion might be unduly restrictive. Therefore, § 3.705 is being amended to permit 0.5 steradians of obstruction without limitation as to direction. _Although Part 3 requires satisfactory airplane ground handling characteristics in crosswind velocities up to 0.2 Vs), there are no provisions to inform the pilot of this capability. Since the safe operation of an airplane requires knowledge of the airplane’s capabilities, § 3.771 is being amended to require that the demonstrated crosswind velocity be included on the airspeed placards specified for all airplanes, The airspeed placards now required by Part 3 do not include certain operational speed information considered essential for airplanes weighing more than 6,000 pounds. These speeds include the recommended climb speed, best angie of climb speed, engine-inoperative climb speeds, and approach speeds. In addition, supplementary information regarding the airplane configuration, power, etc., is necessary to describe the conditions for which these speeds can be used. It is not considered practical to include all of this information on @ cockpit placard. The detailed supplementary information should be included in a separate source which is readily available to the pilot. The Airplane Flight Manual procedures section is considered satisfactory for this purpose. Therefore, § 3.771 is being amended to require the climb and approach speeds placard for airplanes weighing more than 6,000 pounds, and