Status report on the evaluation of road load determination (RLD) using a “wind tunnel plus chassis dynamometer” versus “coast-down” methodologies to enable a wind tunnel plus coast-down method in GTR 15 and on comparison of running resistance measured on a chassis dynamometer by ISO 10521-1 methods (stabilized speeds) and by deceleration (short method).

Progress reports from TUG (chassis dynamometer corrections) and TNO (coast down corrections) covering preliminary results (as of 27.03.2014).

Initial material for deliberations on road load curve determination.

WLTP Phase 1b: Generic formula for hydrocarbon density

Real-time tailpipe ammonia measurements from vehicles tested over the new Worldwide harmonized Light-duty vehicle Test Cycle (WLTC)

Definition of wind tunnel for road load determination (Open Issues #10 and #18).

Proposal on a family definition for road load determination.

Discussion paper on the use of the torque meter in the WLTP coast-down methods to measure the running resistance as part of the road load determination. This document summarizes the views of the special ad hoc group formed to consider this issue.

Discussion paper on “open issue 13” (and 11) concerning corrections for wind conditions that impact coast down tests and times for road load determination and ultimately the road load settings of the chassis dynamometer. This document summarizes the views of the special ad hoc group formed to consider this issue.

WLTP drafting committee working document with corrections to the text of GTR No. 15.

Study on applicability of driving index (defined in SAE J2951) to WLTP test cycle.

Supplemental Test for determination of CO2 emissions under representative regional conditions

Heinz Stephen update on efforts to research and resolve open issues.

Proposal to maintain regulatory language to ensure that vehicles cannot be mis-fueled with a fuel (diesel, leaded or unleaded gasoline, etc.) other than that for which the vehicle is designed.

Discussion of utility factors used in weighting emissions and fuel consumption. Utility factors are ratios based upon driver statistics and vehicle ranges recorded by off-vehicle charging (OVC) hybrid electric vehicles (HEV) (i.e., plug-in hybrid electric vehicles) in charge-depleting and charge-sustaining modes.

ACEA proposes to align the GTR text with the HEV definition used in the EC directive 692/2008/EC (Type-approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6)).

Proposal to refine the selection of reference speeds for the road load curve determination (Open Issues List Item 12: Coast down procedure (Annex 4)).

Letter raising concerns regarding misinterpretation of the definition of a hybrid electric vehicle and resultant misapplication of approval requirements.

Table of items for resolution in phase 1b in the development of the light vehicle emissions and fuel consumption global technical regulation.

Presentation on the use of “sailing” technologies to reduce CO₂ emissions and raising a question over the ability of the WLTP test cycle to account for the effect of sailing on vehicle emissions and fuel consumption performance. Sailing involves the decoupling of the engine from the drive shaft, enabling hybrid vehicles to cruise (or “sail”) on battery power alone until such time as the engine needs to be restarted to generate electricity and/or resume the torque functions.