AVRO 146- RJ 85 V speeds computation
 

Hi
I am not an AVRO 146-RJ 85 driver, furthermore I´m a retired airline pilot for some years, doing some consulting . I have read all the ops. manuals for the type; looking for a procedure or method to re-compute the T.O. speeds in the "speed booklet" for an intersection take off.
Anybody will care to enlighten me
Thanks.

Speeds on the speed cards relate to weight only. If you want to calculate V speeds for a particular runway (full length or intersection) then you need to do a full performance analysis taking into account runway length, slope, obstacles etc.

Thanks for your reply.
Then , what is the use of the speed cards based on wheight only , if there is the need for manual calculation of v speeds for diferent scenarios, namely: intersection , wet runway, contaminated runway, different Altitude apt. Specific runway etc etc.?
Is it fair and legal to use only speed cards all the time in disregard for all this variations?

To clarify, the only speed that varies for a given weight is V1.

Where I work we have tabulated performance data for the runways we operate from. We go into the charts using the current ambient conditions, including flex temperature if applicable, and find out what take-off weight can be used with those conditions. The weight in the chart has a V1 that applies to that runway and that weight. Provided our actual weight is lower than the chart weight, we use Vr, V2, Vfto, and Ver speeds from the speed card for our actual weight. V1 is the lower of the number from the RTOW tables or Vr. Sometimes there is a split between V1 and Vr sometimes they are the same. There is only a significant split on a short, wet runway with minimal obstacles in the departure path.

Assuming we can take the same weight from full length or an intersection, the only variation may be in the V1, all other speeds come from the card.