Aircraft Types and Sub-types
Aircraft types
Aircraft in photos are identified by type (for example, Boeing 747) and sub-type (Boeing 747-400). Only the sub-type is shown under image thumbnails so as not to overload the search results page, but both are shown in the image display window.
It is not always easy to decide what constitutes a distinct aircraft type. Manufacturers often give different names to closely related models while marketing them as a single family of aircraft. In such a case we usually combine the models as a single aircraft type (for example, Bombardier CRJ700/900/1000 or ATR 42/72) and we list the individual models as sub-types.
Aircraft sub-types
Aircraft sub-types or variants are important but can get complicated. Our policy is to keep them simple where we can because we believe that for most of our clientele, user-friendliness trumps detail. Here are examples of how we go about it:
- In the case of light planes, we identify sub-types (if at all) if they embody important design changes or if they are given distinct names by the manufacturer.
- In the case of airliners, we stick to broad variants (such as Airbus A340-300) rather than precise model numbers (A340-313X).
- Airliner variants often come in basic or extended-range options. We take the lead from the manufacturer in deciding whether to identify the latter as separate sub-types. Boeing makes a clear-cut distinction (for example, 777-300 and 777-300ER) while Airbus does not. So we do likewise in each case.
- Freighter variants of airliners, especially Boeings, are officially designated with a variety of suffixes such as 757-200PF, 747-200SF, 747-400BCF. We have taken a deep breath and opted to substitute all of these with a simple "F" designation (e.g. 757-200F). We have kept the official designation only for specialised adaptations such as the 737-300QC or the 747-400M.
- Where we combine differently-named aircraft models together as a single type, as in the Bombardier CRJ example mentioned above, we limit sub-types to individual models e.g. CRJ900 and do not distinguish between variants of the same model (hence no CRJ900ER). Here again, however, we make exceptions where variants are particularly important to the manufacturer's marketing efforts.
Manufacturer name changes
Some aircraft have changed their manufacturer during production as a result of corporate mergers and takeovers. For example, General Dynamics designed and developed the F-16 fighter but later sold the production line to Lockheed Martin. This is what we do in such cases:
- In the "browse by aircraft type" section of Touch The Skies, we list aircraft types by the most recent manufacturer - in this case, Lockheed Martin F-16. This is the aircraft type which will appear in the image display window for all F-16 photos.
- We add the same aircraft type to the homepage quick search menu. Here we also add a "shadow" entry using the name of the former manufacturer (General Dynamics F-16) to cater for anyone who is not up to date. You can search under either entry in the quick search menu and retrieve all F-16 photos.
- We list individual sub-types differently according to which manufacturer is usually associated with each: thus General Dynamics F-16AM and Lockheed Martin F-16C. But all F-16 sub-types will appear in the quick search menu regardless of whether you select General Dynamics F-16 or Lockheed Martin F-16 as the aircraft type.
Licence-built aircraft
There is also the issue of aircraft built under licence by yet another manufacturer. Our preference is to stick to the main manufacturer: thus we list Dutch F-16AMs under General Dynamics rather than Fokker, the company which actually built them. However, we make an exception where licence-built aircraft represent a distinct sub-type. For example, we refer to Embraer's Tucano trainer in Royal Air Force service as the Short Tucano T1.
In such instances we might also add a "shadow" aircraft type entry in the quick search menu using the licenced manufacturer's name, to cater for people who might not know that a plane built by one company was actually developed by another. Thus you can look up the Tucano in the quick search menu under both Embraer and Short.