Narrative:

I was getting vectors to the final approach course for the ILS and the controller asked me what my maximum speed could be for spacing. I told him 150 KTS; which is 30 KTS faster than I would typically fly the approach; but would allow him to more easily space me in with the prevailing turbojet traffic. I had 12;000 ft of runway and I was confident that I would be able to slow the airplane down for a safe landing. That was; in fact; the case. However; the controller turned me onto the final approach earlier than I expected and at that turn to intercept the ILS there was a hard altitude limit; 2;200 ft. I'd just been given an expedite descent command by the controller from 3;000 to 2;200 ft; and I underestimated how much power it would take to arrest the descent at the airspeed I was holding. I descended through the hard altitude; 2;200; while trying to arrest the expedited descent. I then added power and climbed back up as rapidly as I could without compromising my airspeed too much. The controller never said a word about the altitude deviation. I realize now that I was trying to juggle a lot of differences in my typical operating procedures for an ILS approach at one time. I would have been wiser to have told the controller what my typical approach speed was (120 KTS) and let him figure out the math on how to work me in by making a larger space for me in the traffic flow. In IMC it is not a good time to experiment with new techniques for flying the airplane. I know that now.

Related reports:

Google
 

Original NASA ASRS Text

Title: An RV-10 pilot was asked to keep the aircraft's speed up in order to sequence into a Class B airport with jet traffic and in the descent overshot the assigned altitude because of an unusual power requirement to level off.

Narrative: I was getting vectors to the final approach course for the ILS and the Controller asked me what my maximum speed could be for spacing. I told him 150 KTS; which is 30 KTS faster than I would typically fly the approach; but would allow him to more easily space me in with the prevailing turbojet traffic. I had 12;000 FT of runway and I was confident that I would be able to slow the airplane down for a safe landing. That was; in fact; the case. However; the Controller turned me onto the final approach earlier than I expected and at that turn to intercept the ILS there was a hard altitude limit; 2;200 FT. I'd just been given an expedite descent command by the Controller from 3;000 to 2;200 FT; and I underestimated how much power it would take to arrest the descent at the airspeed I was holding. I descended through the hard altitude; 2;200; while trying to arrest the expedited descent. I then added power and climbed back up as rapidly as I could without compromising my airspeed too much. The Controller never said a word about the altitude deviation. I realize now that I was trying to juggle a lot of differences in my typical operating procedures for an ILS approach at one time. I would have been wiser to have told the Controller what my typical approach speed was (120 KTS) and let him figure out the math on how to work me in by making a larger space for me in the traffic flow. In IMC it is not a good time to experiment with new techniques for flying the airplane. I know that now.

Data retrieved from NASA's ASRS site as of April 2012 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.