I think it's important to set clear expectations of what activities are to be completed by all. Team meetings are a great platform to share these expectations and ensure everyone is on the same page. If individuals continue to lack initiative in their roles, it is on the manager to address these concerns during 1:1s as it could ultimately impact that individual's year end review. If the director himself is the one that does not support such changes it can get messier and more complicated however if the product is at risk, it is definitely a good idea to contact upper management out of good conscience. 

In terms of enlightening the manager to the importance in QC and regulatory roles, there would need to be a reason why a project is being impacted significantly due to a loss in those pipelines. There are times that one can say it is not working, but unless there is a visible loss for their team, leaders may not think of the issue as an actual risk their project. If the director does not support the manager, that would be a discussion between the individuals on why some ideas clash. Of course there may be a disconnect between a younger manager and older direction, but they should be well enough into their careers that there should be a reasonable dialogue they are able to communicate with one another to get their points across. Upper management shouldn't be involved unless absolutely necessary as this can hurt the culture and morale of the company if it seems there is a large need for a senior director or VP to mediate a larger discussion unless there is a probable cause or HR violation. 

A division between the whether or not a decision is the correct choice should ideally be brought up in a group setting to allow for the most back and forth with a new idea. However, if that is not possible 1:1 time with your direct supervisor should be made in order to quickly and clearly "air out" any issues you may have with the current approach. If you feel your opinion is being ignored by direct management and it is integral that there should be a change, then 100% upper management should be contacted in order to get a final say on the topic. The debate between young and old minds is one as old as time. Newer opinions should be welcomed for a fresh perspective but by default senior members should lead the way with their experience in routines that work.

I have noticed that in recent times most companies are trying to be more inclusive of diverse perspectives, including younger professionals, although there are definitely still those who feel entitled due to their seniority within the company. A new manager will have to be able to encourage new hires and younger employees to provide and contribute to project discussions as well as amplify their ideas and guide them in communicating it to a more senior level audience. Additionally, a good manager should stand behind his/her direct reports and their decisions/ideas if they believe in it. I have personally seen situations where a young employee was supported by their manager, even though the director was not onboard with the decision. In this case, the manager reached out to other directors who had a stake in the decision and gave the employee the chance to pitch their idea to a wider audience, eventually the idea was approved and it helped ensure product quality. This typically works better in a matrix organization however. For a company with a functional organizational structure, if the situation is very serious and can't be resolved through regular communication, upper management must get involved.

This is a fantastic topic. Like @nm523, I have also noticed a push to incorporate diversity in thought in the workplace. The way my company managed this generational gap was to give "Senior" technical positions for the more experienced staff. This gave the younger employees opportunities to work in the day to day while consulting the more experienced employees for guidance and technical approval for more complex tasks.

Proper communication of roles and expectations like @ridmehta stated, as well as support and mentorship by a competent manager as @Tamanna and @anthonynjit stated, are crucial to mediate the flow of information between junior and senior employees. Otherwise, the rift described by @Pedro F. in the prompt is unlikely to be mended as it relies on employees' altruism and instincts. In my experience, employees are more likely to avoid conflict and let the rift grow.

This is a common scenario in corporate organizations because of the age difference that comes with their experience levels as well as their different styles of working. In this scenario, what usually helps is to hold a meeting between the individuals involved and to communicate the issues out so that there isn't miscommunication, as well as get HR involved if possible in order to have all the issues addressed and to act as a mediator. Working new at a company is a new opportunity where there are different issues that can arise, and this transition shouldn't be stressful, but a company is bound to have these issues even if age isn't an issue. Another thing that can be changed is that older people can mentor younger people if possible, because this would help things work out smoothly. Working with older management is good because they have experience working with different things, and this knowledge can be passed down to younger people. The director should work together with the manager and address concerns that arise, such as whether there is a better way to conduct tests or any other type of issue. Getting upper management involved should be the final resort if all options were exhausted, because this would show upper management that working with others isn't something the manager can do, which doesn't reflect well on all those involved.

Similar to previous replies, I also believe that contacting upper management is a last resort. Involving upper management in this type of situation reflects poorly on the communication skills within teams. This issue can be resolved through better interpersonal communication within the department. A new manager could resolve this current division through encouraging more open collaboration through team meetings. A more positive work culture can begin when the effort to create an open dialogue is initiated openly by an authority figure in the work environment. Prior to the initial meeting, this new manager could speak one on one with both the senior staff and new techs to gain better insight into the general consensus of each group. Such meetings would ensure the manager has a better idea of how to address the underlying issue within the department. In addition, the new manager could also review the efficiency and quality of older standard and newer techniques. This process may be done with consultation with quality experts. Doing so will allow steps to be taken to optimize the function and task process. Providing objective evidence of the equivalency or imbalance of the techniques will sway employees to be better informed in the advantages and disadvantages of each approach.

As stated in other responses, I think communication and setting expectations are of utmost importance. When a new manager is assigned to a team, it is important that this manager gets to know every member of the team, their habits, their strengths, and their weaknesses. Once the manager understands his team, he can set expectations on how the team should work together and clearly define the role of each member of the team. Despite this, there still may be instances during which more experienced members do things the way they are used to and ignore quality control procedures. When this occurs, it is important that the manager talks to the team member about following protocols, and should explain how the team can only work if each member follows the aforementioned expectations. If repeated instances of this occur, there is no issue with approaching upper management for advice or intervention. However, one thing to note is that the manager should also be open-minded and flexible. A lot of senior members may have applicable advice or wisdom that can be integrated into the team's expectations. 

Unfortunately, in this organizational structure, there seems to be several issues. From the favoritism to the lack of concern for quality and regulatory needs, there needs to be a re evaluation of how that department or team is run. The younger employees in the department need to be vocal in expressing their concern to that manager that is mishandling the department. If their voices are not heard, then yes, upper management needs to be contacted. Especially in a biomedical engineering environment, where there are audits and regulation, every action has a future consequence. This manager's neglect of quality will hurt the department and the company in the long run. At that time, it would be asked why did no one say anything or changes were implemented. It is the responsibility of the younger employees in this case to communicate to the older employees the need for equal opportunities for everyone's ideas to be heard. It is also the responsibility of the older employees, who are favorited by the manager, to understand their point of view and not reside in the favoritism. Another issue seems to be the director, who is also in the older category. It is an unfortunate situation, but the director would need to listen to reason from the team and take action against the manager. 

I think going above your management to senior management is usually a bad idea, and can engender negative work environments. If you believe as a manager you can implement certain techniques and processes to increase productivity and results, then you should pitch these ideas to your supervisor and implement them if allowed, even if only for a trial period. After a trial present the hopefully upgraded product to your supervisors to show why it should be adopted at large by the rest of the company.