> Not an aircraft safety expert but I am curious if shifting the wires may not introduce more potential issues in existing planes, as the existing risk factor seems to be proven low (i.e. they are not requiring all 737-NG airframes to have the work)
The 737-NG was introduced in 1997, one year before the new regulations went into effect so it's grandfathered in. Seeking to have the 737-NG retrofitted would be like requiring all cars without airbags to be retrofitted.
What Boeing did with the 737-Max through out it's certification process was argue that it was so similar to the 737-NG that it should be grandfathered into certifications as well. This is done in a lot of industries where certification or regulatory approval is costly and complex, regulators offer a Me-Too path to certification where you argue that your product is based upon or similar enough to an existing product that only the differences need scrutiny. By going this route, Boeing was able to avoid redesign and retooling for things like the wiring harnesses which saved cost and time to market.
Now that the 737-Max is having to be re-certified, AND Boeing's delegated authority to self-certify has been revoked, the FAA is going over everything. The wiring harnesses which were Me-Too'd, aren't in compliance with 1998 requirements. Boeing is trying to argue that the 737-NG has proven the design safe and thus the new requirements shouldn't apply.
The 737-NG was introduced in 1997, one year before the new regulations went into effect so it's grandfathered in. Seeking to have the 737-NG retrofitted would be like requiring all cars without airbags to be retrofitted.
What Boeing did with the 737-Max through out it's certification process was argue that it was so similar to the 737-NG that it should be grandfathered into certifications as well. This is done in a lot of industries where certification or regulatory approval is costly and complex, regulators offer a Me-Too path to certification where you argue that your product is based upon or similar enough to an existing product that only the differences need scrutiny. By going this route, Boeing was able to avoid redesign and retooling for things like the wiring harnesses which saved cost and time to market.
Now that the 737-Max is having to be re-certified, AND Boeing's delegated authority to self-certify has been revoked, the FAA is going over everything. The wiring harnesses which were Me-Too'd, aren't in compliance with 1998 requirements. Boeing is trying to argue that the 737-NG has proven the design safe and thus the new requirements shouldn't apply.