Following 156 hours of ground runs and the receipt of a test certificate from the Ministry of Supply on 28 January 1947, two Theseus engines were fitted in the outer positions of a four-engined Avro Lincoln for air tests.
Setelah 156 jam tanah berjalan dan penerimaan sertifikat uji dari Departemen Supply di 28 Januari 1947, dua mesin Theseus yang dipasang di posisi luar empat bermesin Avro Lincoln untuk tes udara.