Vertical provides details on prototype crash


Vertical Aerospace has revealed details about the sequence that preceded its prototype VX4 crash earlier this month.

The novel aircraft encountered an unexpected fault during a flight test which caused it to enter a “stable descent”, before being damaged on impact with the ground. The test was carried out to get a picture of how the aircraft performed outside of its expected operating conditions before its planned retirement. 

The firm said in a press release issued today that it believes transparency and openness is fundamental to the safety of aerospace. Vertical also said it intends to provide a further full update to the industry on the incident once the AAIB’s investigation has concluded. 

That has now commenced following Vertical’s own in-house investigation and report submitted to the AAIB which found the root cause to be a fault with a bonding issue within the propeller blade. This “Generation 1” propeller had already been redesigned prior to the incident and it has now been removed from all future aircraft, said the firm.

Stephen Fitzpatrick, Vertical founder and CEO, said: “While a fault of any sort is disappointing, it is not wholly unexpected at this stage of testing a novel aircraft. I am pleased that as a result of our expert team we have isolated the cause of the fault and been able to provide the AAIB with our report within 14 days of the incident.

“Our planned second upgraded prototype, which will include most of our top tier partners’ technology, will have us in the air early next year and we remain on track for our certification timelines,” added Fitzpatrick.

The assembly of a second “significantly more advanced” full-scale VX4 prototype is underway at GKN Aerospace’s Global Technology Centre. Its components will include technology from most of Vertical’s certification partners: Honeywell, GKN Aerospace, Hanwha, Solvay, Leonardo and Molicel. An additional, identical full-scale aircraft has also now been approved and is expected to be flying in the second half of 2024. 

The aircraft involved in the incident will be used in further ground tests but will not be repaired to an airworthy standard.

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