Note 16 - Segment Reporting and Sales by Major Customer - Schedule of Revenue by Major Customers by Reporting Segments (Details) - Revenue Benchmark [Member] - Customer Concentration Risk [Member]	12 Months Ended
Apr. 30, 2023	Apr. 30, 2022
Aerospace Products [Member]
Aerospace Products – one customer in 2023, two customers in 2022	14.30%	25.70%
Professional Services [Member]
Aerospace Products – one customer in 2023, two customers in 2022	0.00%	0.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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