Vmc ground

[s3jetman]

Could someone give me a definition of Vmc on the ground? I heard it was on the Pinnacle interview and just wanted to be prepared.

Thanks In Advance

 

[Andy Neill]

I would refer you to 25.149e


http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=3c8414fa16febb5a314621dd65e6e520&rgn=div8&view=text&node=14:1.0.1.3.10.2.156.24&idno=14

which says:

VMCG, the minimum control speed on the ground, is the calibrated airspeed during the takeoff run at which, when the critical engine is suddenly made inoperative, it is possible to maintain control of the airplane using the rudder control alone (without the use of nosewheel steering), as limited by 150 pounds of force, and the lateral control to the extent of keeping the wings level to enable the takeoff to be safely continued using normal piloting skill. In the determination of VMCG, assuming that the path of the airplane accelerating with all engines operating is along the centerline of the runway, its path from the point at which the critical engine is made inoperative to the point at which recovery to a direction parallel to the centerline is completed may not deviate more than 30 feet laterally from the centerline at any point. VMCG must be established with—
(1) The airplane in each takeoff configuration or, at the option of the applicant, in the most critical takeoff configuration;

(2) Maximum available takeoff power or thrust on the operating engines;

(3) The most unfavorable center of gravity;

(4) The airplane trimmed for takeoff; and

(5) The most unfavorable weight in the range of takeoff weights.