C172 pilot entered class B airspace without the permission of ATC.

Attributes
ACN	497134
Time
Date	200012
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ord.airport
State Reference	IL
Altitude	msl bound lower : 3500 msl bound upper : 7500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : c90.tracon tower : iad.tower
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	None
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 25 flight time total : 600 flight time type : 100
ASRS Report	497134
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	airspace violation : entry non adherence : far non adherence : clearance non adherence : published procedure
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance controller : issued advisory flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance Chart Or Publication
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While in cruise from otm to pwk over dekalb, contacted ord approach for permission to cross class B airspace. Permission denied by ATC. ATC advised me to 'stay clear of class B airspace.' I began descent to go under class B airspace, but due to strong tailwind and miscalculation, I entered class B airspace during descent. Was advised by ATC that I was in class B airspace and directed to 'VFR descent to 3500 ft or lower.' I descended immediately to 3500 ft and asked ATC to identify my location. ATC provided location as 17 mi northwest of ord. I continued flight with advisories from ATC to pwk with no further events. Factors that caused error: 1) higher than normal ground speed. 2) unable to pick out ground landmarks on terminal area chart due to development/construction not shown on chart. 3) unexpected response from ATC -- denied entry into class B airspace. 4) improper decision by pilot to descend too slowly.

Original NASA ASRS Text

Title: C172 PLT ENTERED CLASS B AIRSPACE WITHOUT THE PERMISSION OF ATC.

Narrative: WHILE IN CRUISE FROM OTM TO PWK OVER DEKALB, CONTACTED ORD APCH FOR PERMISSION TO CROSS CLASS B AIRSPACE. PERMISSION DENIED BY ATC. ATC ADVISED ME TO 'STAY CLR OF CLASS B AIRSPACE.' I BEGAN DSCNT TO GO UNDER CLASS B AIRSPACE, BUT DUE TO STRONG TAILWIND AND MISCALCULATION, I ENTERED CLASS B AIRSPACE DURING DSCNT. WAS ADVISED BY ATC THAT I WAS IN CLASS B AIRSPACE AND DIRECTED TO 'VFR DSCNT TO 3500 FT OR LOWER.' I DSNDED IMMEDIATELY TO 3500 FT AND ASKED ATC TO IDENT MY LOCATION. ATC PROVIDED LOCATION AS 17 MI NW OF ORD. I CONTINUED FLT WITH ADVISORIES FROM ATC TO PWK WITH NO FURTHER EVENTS. FACTORS THAT CAUSED ERROR: 1) HIGHER THAN NORMAL GND SPD. 2) UNABLE TO PICK OUT GND LANDMARKS ON TERMINAL AREA CHART DUE TO DEVELOPMENT/CONSTRUCTION NOT SHOWN ON CHART. 3) UNEXPECTED RESPONSE FROM ATC -- DENIED ENTRY INTO CLASS B AIRSPACE. 4) IMPROPER DECISION BY PLT TO DSND TOO SLOWLY.

Data retrieved from NASA's ASRS site as of July 2007 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.