Dear Dr. Gudmundsson’s thanks for your job. I’ve got an light a/c Vulcan c100rg since 2005 that now I’m modifying. I always have had problem by the low authority of the tail. More precisely during take off and when try to keeping the wing slip which it is impossible to maintain, the a/c return straight even with full rudder. I made a comparison with similar a/c and realise that the total Surface is smaller and the rudder much smaller. According to you do I doing right trying to increase, keeping proportion, the surface of the rudder? What is the right way to face and correct the problem (or finding a better compromise)? Thank you Salvo
Hi Salvo. Thank you for your message. Unfortunately, I have to be very careful and not speculate on makes and models of aircraft without knowing more details (and then not in public). I am not familiar enough with the Vulcan to comment on it specifically. In general, enlarging the vertical tail of an existing airplane will increase its directional stability. How this affects controllability depends on the size of the rudder (will it change too?) and the control horn (assuming it has one). But there are other contributions that must be considered too. Enlarging the vertical tail increases aerodynamic shear, bending, and torsional loads, so one must confirm if the fuselage can still react this. Also, a larger vertical tail means more mass and a large mass change may reduce the aircraft's flutter speed. This speed must typically be larger than 1.2 x dive speed. Unfortunately, enlarging the vertical tail may constitute a significant change and, thus, you should approach it with great care. I suggest you consult the airplane manufacturer and get their insight. Sorry I can't be of more help and hope you understand why. Best wishes.
@@dr.gudmundssonaircraftdesign hello Dr. Thanks for your replay, unfortunately the a/c manufacturers doesn’t exist anymore so I’ll take my risk. I’ve really appreciated your suggestions, aware of the extreme delicacy of the issue. I’ll be careful by enlarging just the rudder until reaching the right proportion with the actual fin. I’ll also statically balance the rudder, the old was lacking. We will see Best regards Salvo
Thank you.
👍
@abdbot3000 You're welcome.
Thanks Doctor.
You're welcome. :-)
Dear Dr. Gudmundsson’s thanks for your job. I’ve got an light a/c Vulcan c100rg since 2005 that now I’m modifying. I always have had problem by the low authority of the tail. More precisely during take off and when try to keeping the wing slip which it is impossible to maintain, the a/c return straight even with full rudder. I made a comparison with similar a/c and realise that the total Surface is smaller and the rudder much smaller. According to you do I doing right trying to increase, keeping proportion, the surface of the rudder? What is the right way to face and correct the problem (or finding a better compromise)? Thank you
Salvo
Hi Salvo. Thank you for your message. Unfortunately, I have to be very careful and not speculate on makes and models of aircraft without knowing more details (and then not in public). I am not familiar enough with the Vulcan to comment on it specifically. In general, enlarging the vertical tail of an existing airplane will increase its directional stability. How this affects controllability depends on the size of the rudder (will it change too?) and the control horn (assuming it has one). But there are other contributions that must be considered too. Enlarging the vertical tail increases aerodynamic shear, bending, and torsional loads, so one must confirm if the fuselage can still react this. Also, a larger vertical tail means more mass and a large mass change may reduce the aircraft's flutter speed. This speed must typically be larger than 1.2 x dive speed. Unfortunately, enlarging the vertical tail may constitute a significant change and, thus, you should approach it with great care. I suggest you consult the airplane manufacturer and get their insight. Sorry I can't be of more help and hope you understand why. Best wishes.
@@dr.gudmundssonaircraftdesign hello Dr. Thanks for your replay, unfortunately the a/c manufacturers doesn’t exist anymore so I’ll take my risk. I’ve really appreciated your suggestions, aware of the extreme delicacy of the issue. I’ll be careful by enlarging just the rudder until reaching the right proportion with the actual fin. I’ll also statically balance the rudder, the old was lacking. We will see
Best regards
Salvo