CITATION 750 HAS A HDG DEV DURING THE LOUPE1 SID.

Narrative

WE WERE DEPARTING SJC RWY 30L ON THE LOUPE 1 DEP. AFTER REVIEWING THE SID WE DECIDED TO FLY THE FLT DIRECTOR IN LNAV TO MAKE SURE WE DIDN'T MISS THE SJC 1.8 DME. WE ALSO HAD IT BACKED UP. IT WAS A VISUAL DAY. AS WE CLBED OUT; WE TURNED AT 1.8 DME NW OF SJC. THE HDG BUG WAS SET TO 120 DEG HDG. THE FMS NEEDLE ALSO POINTED TO 120 DEGS. AS WE WERE IN THE TURN THE ACFT ACCELERATED AS OUR FMS DICTATED. WE WERE CLR OF ALL OBSTACLES AND STARTED TO LEVEL. THE ACFT TURNED PAST 120 DEG HDG TO A 150 DEG HDG. WE SAW THIS AND TURNED BACK TO 120 DEG HDG. ATC ASKED WHAT HDG WE WERE ON AND WE SAID 120 DEGS. HE THEN ASKED IF WE WERE ON A 150 DEG HDG AND WE SAID YES. HE ASKED WHAT AVIONICS WE HAD. WE TOLD HIM HONEYWELL. HE SAID THEY HAVE HAD GULFSTREAMS GOING THROUGH THE 120 DEG HDG; AND TRYING TO FIGURE OUT IF IT WAS THE SAME AVIONICS. WE LATER DECIDED TO CALL NORCAL DEP. AFTER TALKING TO THEM; WE FOUND OUT THEY NEED THE TURN TO BE KEPT TIGHT; DUE TO OBSTACLE CLRNC AND CLASS B AIRSPACE. NOWHERE ON THE SID DOES IT STATE A TURN RADIUS NOR A SPD RESTR. BEING VFR WE WERE ABLE TO MAINTAIN VISUAL SEPARATION FROM ALL OBSTACLES. I FEEL THEY NEED TO PUT A SPEED RESTR ON THIS SID; ESPECIALLY FOR FASTER ACFT SUCH AS THE GULFSTREAM AND CITATION X'S. THEN AS PLTS WE WOULD BE ABLE TO KNOW THEY NEED A TIGHT TURNING RADIUS AND WE WOULD BE ABLE TO SPD INTERVENE THE FMS; SO AS NOT TO ACCELERATE UNTIL WE ARE PAST THE 047 DEG RADIAL OFF OF SJC OR ATC ADVISES. I BELIEVE THIS WOULD HELP ATC WITH SEPARATION AND SPD UNDER CLASS B. THIS ALSO WOULD ALLOW ACFT TO STILL BE ABLE TO CLB AT V2 TO MEET MINIMUM CLB GRADIENTS IN IFR. (IT WOULD NEED TO SAY DO NOT EXCEED 200 KTS; EXAMPLE.) EVEN BEING VFR ALL CLB GRADIENTS WERE MET. I BELIEVE THIS WOULD HELP PLTS WHO ARE UNFAMILIAR AND EVEN ATC. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THEY WERE FLYING THE ACFT IN THE LNAV/FMS MODE AND THE ACFT WILL ONLY GIVE A 25 DEG BANK. AS IT ACCELERATED THE ACFT'S TURN RADIUS WAS NOT ENOUGH AND IT DID OVERSHOOT THE FMS DEPICTED DEP (MAGENTA LINE) AND WAS CORRECTING BACK ON A HDG OF 150 DEGS. THE RPTR HAD DISCUSSED THIS WITH THE OTHER PLT AND THEY DETERMINED THAT THE TURN WAS TOO TIGHT TO FLY IN THE LNAV MODE AND THEY AGREED THEY SHOULD FLY IT IN THE HDG SELECT MODE OR MANUALLY.