• The FAA proposes airworthiness directives for Bell Textron Canada Limited Model 429 helicopters.
• The directives address sliding door jamming issues and require inspections and modifications.
• The FAA also proposes to supersede an existing AD for Leonardo S.p.a. Model AB139 and AW139 helicopters.
• The new AD would require revising airworthiness limitations sections in maintenance manuals.

These proposed airworthiness directives may indicate the FAA's increased focus on addressing safety concerns in helicopter design and maintenance. The requirements for inspections and modifications could suggest a shift towards more proactive safety measures, which may impact the helicopter industry's maintenance and operational costs.