Narrative:

VFR day. Trip to teb. Runway 6/24 closed. Advised on checkin with approach to expect ILS 6 circle to rwy 1. Told to descend to 2000 ft and turn to 030 to intercept. Maintain 2000 until established cleared for the ILS 6 circle to 1 at teb. Intercept the localizer and capture glide path (gp) as I approach dandy on the localizer and gp I begin to realize we are not going to be close to the mandatory 1500 crossing despite being on the gp. I click off autopilot and dive below the gp. I am no longer stabilized and am below the gp in a turbojet aircraft. Thank god it was VMC. I believe I crossed dandy anywhere between 1450 to 1550 feet. Continued to torby and executed an uneventful circle to rwy 1. I was never told by ATC to cross dandy at a specific altitude nor was anything said to me while after crossing dandy.I believe that to clear a pilot for the ILS and then to have the pilot go intentionally below the gp is contrary to the regs and training. This is a confusing approach for anyone not familiar with it. My mistake was assuming the gp would bring me across dandy at 1500 feet. The mandatory note on the plate was (I thought) to emphasize that the pilot has to be on the gp.if that was IMC and being that close to the ground and the ridgeline I wonder if my egpws would have gone off?I will not be caught unawares again as regarding that situation; each time I brief a plate I will look for that scenario.

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Original NASA ASRS Text

Title: A Corporate pilot flew the TEB ILS Runway 6; circle Runway 1 but was puzzled because his clearance was maintain 2;000 feet until established. He assumed incorrectly on glideslope would fulfill the mandatory 1;500 feet DANDY constraint but a rapid descent met the constraint.

Narrative: VFR day. Trip to TEB. RWY 6/24 closed. Advised on checkin with approach to expect ILS 6 circle to Rwy 1. Told to descend to 2000 ft and turn to 030 to intercept. Maintain 2000 until established cleared for the ILS 6 circle to 1 at TEB. Intercept the LOC and capture glide path (GP) as I approach DANDY on the LOC and GP I begin to realize we are not going to be close to the mandatory 1500 crossing despite being on the GP. I click off autopilot and dive below the GP. I am no longer stabilized and am below the GP in a turbojet aircraft. Thank god it was VMC. I believe I crossed DANDY anywhere between 1450 to 1550 feet. continued to TORBY and executed an uneventful circle to Rwy 1. I was never told by ATC to cross DANDY at a specific altitude nor was anything said to me while after crossing DANDY.I believe that to clear a pilot for the ILS and then to have the pilot go intentionally below the GP is contrary to the regs and training. This is a confusing approach for anyone not familiar with it. My mistake was assuming the GP would bring me across DANDY at 1500 feet. The mandatory note on the plate was (I thought) to emphasize that the pilot has to be on the GP.If that was IMC and being that close to the ground and the ridgeline I wonder if my EGPWS would have gone off?I will not be caught unawares again as regarding that situation; each time I brief a plate I will look for that scenario.

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.