The French Learners Audio Corpus of German Speech (FLACGS) was recorded to study the quantity and nature of French learners’ pronunciation difficulties in German on a segmental level across three different tasks: word repetition, reading and picture description. The corpus was transcribed manually. The orthographic transcription was automatically aligned with the MAUS-web service. Among others, the data suggests that French learners of German have difficulties with vowel quantity contrasts as well as presence of /h/ onset on a segmental level. Duration is a valid cue to investigate vowel quantity as well as /h/ onset production. The French learners performed well across the tasks on vowel quantity distinction, except for the contrast /a/-/a:/ in the reading task. French learners of German produce identical durations for /a/-/a:/ that neither match the usual short vowel or the long vowel duration. French learners of German might only have one /a/-sound they can produce without any auditory input. That could explain why the duration for /a/-/a:/ is not clearly associated to the short-long vowel duration pattern. The quantity contrast between /a/-/a:/ was well performed by the French learners of German in the repetition task. That result suggests that the omitted contrast in the reading task is not due to erroneous perception. Regarding the /h/ onset, /h/ onset production decreases with higher production complexity in the task. At least three out of four possible /h/ onsets are produced as /h/ onset by French learners. The others are widely replaced by empty onsets, about 15% of the uttered words with /h/ onset, except for the reading task. In reading, French learners prefer a glottal stop to an empty onset. This result could be explained by decoding efforts. In reading and picture describing, French learners of German tend to produce longer /h/ onsets than German natives. The French learners may aim to be unambiguous by insisting on the first segment of the word. Across the tasks, French learners of German behave native-like for the vowel quantity contrast and the /h/ onset in the repetition task. This result suggests that French learners of German perceive vowel quantity and /h/ onsets well. The speech corpus is not a resource that allows us by itself to conclude whether the participants have achieved contrastive perception of the vowel quantity contrast or the /h/ onset, however.