Masters Theses

Date of Award

5-2002

Degree Type

Thesis

Degree Name

Master of Science

Major

Aviation Systems

Major Professor

Fred Stellar

Committee Members

Ralph Kimberlin, U. Peter Solies

Abstract

Vertical replenishment (VERTREP) of underway fleet naval vessels by helicopter is the primary mission of the MH-60S helicopter and is absolutely critical to sustaining fleet combat readiness at sea. The effectiveness of the MH-60S helicopter in conducting this crucial mission is directly dependent upon its ability to launch from and recover to the delivery ship under a wide range of wind-over-deck (WOD) conditions.

This thesis is an investigation of the effects of relative winds over the deck on the MH-60S helicopter documented during shipboard launch and recovery operations conducted during the initial MH-60S shipboard testing and launch and recovery wind envelope development.

The investigation involved the calculated variation of relative wind-over-deck speed and direction during shipboard launch and recovery evolutions. Effects of the relative winds over the deck on the helicopter during launch and recovery were quantified using pilot rating scales, designed to permit the brief yet accurate characterization of aircraft handling qualities and pilot workload. Build-up flight test techniques were used to mitigate the risk associated with shipboard launch and recovery wind envelope development.

This investigation yielded a satisfactory characterization of the handling qualities of the MH-60S helicopter aboard three different classes of naval vessels. Additionally, it resulted in the establishment of relatively large and operationally flexible launch and recovery wind envelopes for each of these classes of ship, all of which are recommended for employment by the fleet upon introduction of the helicopter.

The investigation also yielded four unsatisfactory pilot-vehicle interface (PVI) deficiencies pertinent to operating the MH-60S helicopter aboard ship. They were related to extremely limited forward field of view (FOV), excessive cockpit vibrations, aft location of the tail wheel, and hazardous strength of the main rotor down wash.

It is the opinion of this author that much can be done to make the immense task of initially qualifying a new helicopter for operations aboard all classes of naval ship safer, and more economical, efficient and logical. It is also the position of this author that this initial MH-60S shipboard test effort did not satisfactorily leverage the massive amount of knowledge pertinent to such an endeavor that currently exists in government, military, civilian and academic institutions of the world interested in this field of study.

If U. S. Navy launch and recovery wind envelope development is to succeed at truly maximizing the shipboard operational capability of a helicopter, more must be done to leverage the tremendous technological advances being made in this and related fields of study, and to employ data already gathered by institutions conducting similar testing.

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