DA900 captain reported they deviated from their cleared track when their honeywell epic equipped air...

Narrative:

We were being vectored north of dallas for our arrival into dal. We had originally been cleared on the JFRYE2 but had been vectored off by regional approach. When we were approximately 20-25NM northeast of the gregs intersection we were cleared directly to gregs and cleared to descend via the JFRYE2 arrival. Due to our position and the location of the subsequent fix; mnkee; the FMS calculated a smart turn north and east of gregs. As we flew closer to gregs; we discovered that the smart turn would be greater than 4NM when abeam gregs. The controller asked us to verify the last clearance; which we did; and we explained the situation. The pilot flying used the heading mode to manually steer the aircraft closer to gregs using the moving map display. The course to mnkee was recaptured; and the rest of the arrival was flown without incident.this scenario is a known issue with the honeywell epic platform. The manufacturer has instructed operators to reset the LNAV bank factor from 7 to 15 to prevent FMS early smart turns. It appears that this setting resets to 7 after base software has been installed because both aircraft I checked had 7 in the LNAV bank factor. This is not an item that is called out to be checked in the expanded power on checks in codde 2; but I will certainly be adding it to my daily checks.

Original NASA ASRS Text

Title: DA900 Captain reported they deviated from their cleared track when their Honeywell Epic equipped aircraft made a wide 'smart turn' during arrival into DAL.

Narrative: We were being vectored north of Dallas for our arrival into DAL. We had originally been cleared on the JFRYE2 but had been vectored off by Regional Approach. When we were approximately 20-25NM northeast of the GREGS intersection we were cleared directly to GREGS and cleared to descend via the JFRYE2 arrival. Due to our position and the location of the subsequent fix; MNKEE; the FMS calculated a smart turn north and east of GREGS. As we flew closer to GREGS; we discovered that the smart turn would be greater than 4NM when abeam GREGS. The controller asked us to verify the last clearance; which we did; and we explained the situation. The pilot flying used the heading mode to manually steer the aircraft closer to GREGS using the moving map display. The course to MNKEE was recaptured; and the rest of the arrival was flown without incident.This scenario is a known issue with the Honeywell Epic platform. The manufacturer has instructed operators to reset the LNAV Bank Factor from 7 to 15 to prevent FMS early smart turns. It appears that this setting resets to 7 after base software has been installed because both aircraft I checked had 7 in the LNAV Bank Factor. This is not an item that is called out to be checked in the expanded POWER ON checks in CODDE 2; but I will certainly be adding it to my daily checks.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1308700
Time
Date	201511
Local Time Of Day	1801-2400
Place
Locale Reference	DAL.Airport
State Reference	TX
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	Falcon 900
Operating Under FAR Part	Part 91
Flight Phase	Descent
Route In Use	Direct STAR JFRYE2
Flight Plan	IFR
Component
Aircraft Component	FMS/FMC
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 116 Flight Crew Total 7890 Flight Crew Type 442
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Clearance Deviation - Track / Heading All Types

DA900 captain reported they deviated from their cleared track when their honeywell epic equipped aircraft made a wide 'smart turn' during arrival into dal.