Kay McNulty

Kay Mc Nulty Source: Wikipedia https://en.wikipedia.org/wiki/Kathleen_Antonelli

Kay mcNulty was a Pioneering Irish America Computer Programmer. She was one of the first women to program the ENIAC computer in the USA in the 1940s.

Irish upbring

Kay was born in Feymore at the foot of Muckish Mountain in 1921 during the Irish war of Independence. Her father James McNulty was imprisoned in the jail in Derry on the day of her birth because of his involvement with the Irish Republican Army.

Muckish Mountain.

In October 1924, on her father’s release the family sailed for America. They set up their new home in Chestnut Hill in a suburb of Philadelphia. Kay attended Parochial grade school and J.W, Hallahan Catholic girls HS in Philadelphia. Kay was only able to speak Irish when she went to America.

After graduation she attended the Chestnut Hill College for Women and continued her maths studies. She was one of only a few women to graduated in 1942 with a Maths Degree.

Graduate in Maths

Keen to put her maths education to go use she applied for a job with the US Civil Services and joined the war effort in June 1942. During the second world war the US army hired women to calculate bullet and missile trajectories at Ballistic Research Laboratory at the Aberdeen Proving Ground in Maryland. Kay and her friend from College Frances Bilas were hired as human computers at a low subprofessional civil service pay grade.

Kay and Frances’s first job was to calculate the ballistics trajectories used for the artillery firing tables, mostly using mechanical desk calculators and large sheets of paper.

In 2010 a documentary Top Secret Rosies: the female computers of WW11 was released. It included in depth interviews with 3 of the 6 female programmers. Kay had already passed away in 2006 so didn’t feature but was remembered as one of the 6 to make a massive impact on the war effort. She also inspired the award winning documentary The Computer in 2013.

Within a few months of starting there were around 75 females working as human computers. Francis and Kay were moved to work on the Differential Analyser working out of the basement of the Moore School.

Differential and ENIAC

The Differential was one of the most sophisticated analogue machines of its time. There were only 3 in the USA and 6 in the world. This new classified project and its machine was able to compute trajectory calculations within an hour which had previously taken up to 40 hours. Kay become supervisor in the Analyser room.

As part of the war effort The Electronic Numerical Integrator and Computer was developed to assist with missile and ballistics calculations. Kay also worked on this and become one of its first programmers along with 7 other women from the computer corp. kay is credited with inventing the Subroutine a program to assist in extending the capacity of the ENIAC to compute some trajectories.

Married life

In 1948 Kay married the ENIAC co-inventor John Mauchly. She went on to have 5 children but was known to have helped program for her husband from home working on the software design for BINAC and UNIVAC AC 1 computers which were designed by John. They settled in Little Linden, Amber, Pennsylvania. John passed away in 1980.

In 1985 she re-married photographer Severo Antonelli. He suffered from Parkinson’s Disease and died in 1996.

Watch this video made by Glass Mountain Digital on the exceptional Kay McNulty.

A tribute to Kay McNulty.


After John’s death she carried on the ENIAC legacy by authorising articles and giving talks along with the other female programmers.

In 1997 before she died she was inducted into the Women in Technology International Hall of Fame along with the other ENIAC programmers.

In 2017 10 years after her death she was honoured by DCU who named their computing building after Kathleen Kay mcNulty.

In 2019 the Irish Centre of High End Computing ICHEC at the University College Galway named its new Waterford based primary supercomputer after her.

A portrait of Kay by Jim Fitzpatrick was unveiled in DCU as part of the Accenture Ireland’s WomenonWalls exhibition in March 2021. The portrait is temporarily installed in the DCU Stoke Building but it will move to the university’s new Future-Tech building which is currently under construction at the Glasnevin campus and will become one of its flagship buildings for science, computing and engineering disciplines. A perfect home for Kay!

Memorial Plaque

On April 3rd 2023 a commemortive memorial Plaque honouring Kay McNulty’s life and achievements was unveiled in Creeslough. Joined at the unveiling was her son, Grand-daughter Naomi, great grandson Callum. Who travelled from the USA.

Members of Creeslough Community Association along with Eamonn McFadden who was instrumental in making the memorial a reality.

Published by mairead collett

Living the rural Life in Donegal, raising children and writing about my local area.