A light aircraft pilot encountered severe wake turbulence while entering washington; dc leesburg sfr...

Attributes
ACN	1021421
Time
Date	201206
Local Time Of Day	1201-1800
Place
Locale Reference	JYO.Airport
State Reference	VA
Environment
Light	Daylight
Aircraft 1
Make Model Name	Small Aircraft High Wing 1 Eng Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	Landing Takeoff
Route In Use	Direct
Flight Plan	None
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Multiengine Flight Crew Commercial Flight Crew Flight Instructor Flight Crew Instrument
Experience	Flight Crew Last 90 Days 31 Flight Crew Total 7140 Flight Crew Type 1600
Events
Anomaly	ATC Issue All Types Conflict Airborne Conflict Deviation - Procedural FAR Inflight Event / Encounter Wake Vortex Encounter

Narrative:

The collocations of the jyo sfra maneuvering area gates with the jyo [runway] 17 ILS tend to concentrate the traffic inbound from a northerly and north easterly direction. Traffic uses the ILS; and jyo northerly outbound and north easterly bound traffic using the ILS or the fixes as the sfra boundary in lieu of a ground visual or the aml radials. The aml VORTAC is and has been out of service for a long time. Without aml; if aircraft do not have DME; it is very difficult; due to lack of ground references; to judge the 30 NM arc distance from the dca VORTAC; hence the use of the ILS and the ILS fixes. The traffic concentration provides the opportunity for arrival and departure head on passing traffic; operating in turbulence; and crossing of departing [runway] 35 traffic going north and west and arriving traffic going south and west to enter the pattern for 35 in an area where the class B floor is only 1;500 ft. Some of the turbulence can be significant because most of the large jets and turboprops tend to use the ILS for landing or to side step to the down wind for 35.

Original NASA ASRS Text

Title: A light aircraft pilot encountered severe wake turbulence while entering Washington; DC Leesburg SFRA because most aircraft use the JYO Runway 17 ILS localizer track for SFRA entry because the AML VORTAC is not available to define the areas boundaries when used with the DCA VORTAC.

Narrative: The collocations of the JYO SFRA maneuvering area gates with the JYO [Runway] 17 ILS tend to concentrate the traffic inbound from a northerly and north easterly direction. Traffic uses the ILS; and JYO northerly outbound and north easterly bound traffic using the ILS or the fixes as the SFRA boundary in lieu of a ground visual or the AML radials. The AML VORTAC is and has been out of service for a long time. Without AML; if aircraft do not have DME; it is very difficult; due to lack of ground references; to judge the 30 NM arc distance from the DCA VORTAC; hence the use of the ILS and the ILS fixes. The traffic concentration provides the opportunity for arrival and departure head on passing traffic; operating in turbulence; and crossing of departing [Runway] 35 traffic going north and west and arriving traffic going south and west to enter the pattern for 35 in an area where the Class B floor is only 1;500 FT. Some of the turbulence can be significant because most of the large jets and turboprops tend to use the ILS for landing or to side step to the down wind for 35.

Data retrieved from NASA's ASRS site as of July 2013 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.

A light aircraft pilot encountered severe wake turbulence while entering washington; dc leesburg sfra because most aircraft use the jyo runway 17 ILS localizer track for sfra entry because the aml VORTAC is not available to define the areas boundaries when used with the dca VORTAC.