The Multi-Role Aircraft (MRA)–later Multi-Role Combat Aircraft (MRCA)–which led to the Panavia Tornado was initially an international project made up of West Germany, the Netherlands, Belgium, Italy and Canada to study replacements for their F-104s, with Canada and Belgium departing early on due to concerns that it was too Western Europe-centric and wooing by Dassault with the Mirage 5 respectively. The UK joined looking to replace the Vulcan and Buccaneer, and with the Air Defence Variant (ADV) the Lightning and F-4, whilst the Netherlands left due to the increasing complexity of the aircraft. Putting aside industrial concerns supposing that for various reasons the UK doesn't join the MRCA project would the F-15E have made a viable alternative? I know that it didn't enter service until a decade later but right from the start McDonnell Douglas were touting what would become the E variant, although the US Air Force were studiously uninterested, so the idea is they use interest from the UK as an excuse to develop the variant. The big question is would it would have the range and endurance, not always the same thing, to fill the ADV role covering the G-I-UK gap? I've come across some conflicting numbers when searching. Other questions are would West Germany and Italy continue with the Tornado by themselves? I think they probably would, especially since they wouldn't need to develop the ADV then. Not being too knowledgeable of the MRCA project does anyone know if it was the UK's requirements that pushed the complexity of the aircraft over the line of what the Dutch thought was acceptable or would what West Germany and Italy want from it do that anyway? If the Netherlands stay in it could have knock-on effects for their purchase of the F-16 several years later, probably in terms of numbers.