B737 captain reported sinking below the glideslope on approach to iah in trail of a B777.

Attributes
ACN	1359059
Time
Date	201605
Local Time Of Day	0601-1200
Place
Locale Reference	IAH.Airport
State Reference	TX
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Flight Plan	IFR
Aircraft 2
Make Model Name	B777 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Flight Plan	IFR
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Type 12596
Events
Anomaly	Inflight Event / Encounter Unstabilized Approach Inflight Event / Encounter Wake Vortex Encounter

Narrative:

We were following a B777 to runway 8R in iah. There was a 30 knot quartering tailwind during the approach and our spacing with the heavy started getting closer and closer. Crossing maton; the airplane started to sink below the glide slope and the GPWS was activated. We followed the go-around procedure and came around for a non-eventful visual approach and landing.

Original NASA ASRS Text

Title: B737 Captain reported sinking below the glideslope on approach to IAH in trail of a B777.

Narrative: We were following a B777 to RWY 8R in IAH. There was a 30 knot quartering tailwind during the approach and our spacing with the heavy started getting closer and closer. Crossing MATON; the airplane started to sink below the glide slope and the GPWS was activated. We followed the go-around procedure and came around for a non-eventful visual approach and landing.

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.