Flight crew of an light transport turboprop exceeded maximum airspeed below class B airspace. Approa...

Attributes
ACN	397510
Time
Date	199803
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mem
State Reference	TN
Altitude	msl bound lower : 3000 msl bound upper : 5000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : mem
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	other other : other pilot : atp
Experience	flight time last 90 days : 210 flight time total : 4500 flight time type : 210
ASRS Report	397510
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : less severe non adherence : far other anomaly other anomaly other
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During a scheduled passenger flight from pah to mem, aircraft was flown at 250 KTS below class B airspace. The aircraft involved had been dispatched without a pressurization system per MEL. Due to passenger comfort I decided to begin an early descent to allow for a 300 FPM descent rate. After getting ATC clearance to 3000 ft the first officer proceeded to descend from 5000 ft to 3000 ft at 250 KTS then continued while entering the class B airspace veil. I was in the process of talking to mem company operations on the other radio since we had not been able to get them at the low altitudes. After returning to ATC I was questioned about our speed. After reporting 250 KTS ATC then advised we were below class B airspace. I immediately had the first officer slow to 200 KTS per FARS. Approximately 1 min later ATC advised we had re-entered class B and to resume normal speed. Flight continued to normal landing. With multiple distractions the fact that we were below class B went unnoticed until advised by ATC. These factors included aircraft component inoperative: requiring non standard arrival lower than normal altitudes, which also made radio reception a problem leading to another distraction during approach. This problem could be prevented by requiring ATC to advise prior to operating under class B airspace either penetrating from outside the radius or descending below the floor. Also class B airspace and floors could be depicted on sids, stars and approach charts instead of a separate chart to make them more obvious. Or the airspeed limits could be made uniformly in class B and below.

Original NASA ASRS Text

Title: FLC OF AN LTT TURBOPROP EXCEEDED MAX AIRSPD BELOW CLASS B AIRSPACE. APCH CTLR INTERVENED, AFTER APPROVING THEIR REQUEST TO DSND SLOWLY TO A LOWER ALT, TO ALERT THEM REGARDING THEIR SPD EXCEEDING THAT PERMITTED.

Narrative: DURING A SCHEDULED PAX FLT FROM PAH TO MEM, ACFT WAS FLOWN AT 250 KTS BELOW CLASS B AIRSPACE. THE ACFT INVOLVED HAD BEEN DISPATCHED WITHOUT A PRESSURIZATION SYS PER MEL. DUE TO PAX COMFORT I DECIDED TO BEGIN AN EARLY DSCNT TO ALLOW FOR A 300 FPM DSCNT RATE. AFTER GETTING ATC CLRNC TO 3000 FT THE FO PROCEEDED TO DSND FROM 5000 FT TO 3000 FT AT 250 KTS THEN CONTINUED WHILE ENTERING THE CLASS B AIRSPACE VEIL. I WAS IN THE PROCESS OF TALKING TO MEM COMPANY OPS ON THE OTHER RADIO SINCE WE HAD NOT BEEN ABLE TO GET THEM AT THE LOW ALTS. AFTER RETURNING TO ATC I WAS QUESTIONED ABOUT OUR SPD. AFTER RPTING 250 KTS ATC THEN ADVISED WE WERE BELOW CLASS B AIRSPACE. I IMMEDIATELY HAD THE FO SLOW TO 200 KTS PER FARS. APPROX 1 MIN LATER ATC ADVISED WE HAD RE-ENTERED CLASS B AND TO RESUME NORMAL SPD. FLT CONTINUED TO NORMAL LNDG. WITH MULTIPLE DISTRACTIONS THE FACT THAT WE WERE BELOW CLASS B WENT UNNOTICED UNTIL ADVISED BY ATC. THESE FACTORS INCLUDED ACFT COMPONENT INOP: REQUIRING NON STANDARD ARR LOWER THAN NORMAL ALTS, WHICH ALSO MADE RADIO RECEPTION A PROB LEADING TO ANOTHER DISTR DURING APCH. THIS PROB COULD BE PREVENTED BY REQUIRING ATC TO ADVISE PRIOR TO OPERATING UNDER CLASS B AIRSPACE EITHER PENETRATING FROM OUTSIDE THE RADIUS OR DSNDING BELOW THE FLOOR. ALSO CLASS B AIRSPACE AND FLOORS COULD BE DEPICTED ON SIDS, STARS AND APCH CHARTS INSTEAD OF A SEPARATE CHART TO MAKE THEM MORE OBVIOUS. OR THE AIRSPD LIMITS COULD BE MADE UNIFORMLY IN CLASS B AND BELOW.

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.

Flight crew of an light transport turboprop exceeded maximum airspeed below class B airspace. Approach controller intervened, after approving their request to descend slowly to a lower altitude, to alert them regarding their speed exceeding that permitted.