The model is now complete. Here's a 360 turnaround and some screenshots of the final model. 
The model is nearly finished, and there are only a couple of things to add; A gas cap, some extra detail to the wings and mirroring the wing to the other side. 
In order to create the gas cap, I created a polygon cylinder, scaled and positioned it where I wanted on the plane. I then decreased the amount of sections as I'm going to smooth it later, so the least amount of sections, the smoother it will be. I selected the faces inside the geometry and extruded them inwards. As there isn't enough resolution to work with, I smoothed the object, which gave me more resolution to play with, so I took some of the faces and extruded them out to give the cap more detail. 
The next thing to do was put a bit more detail on the plane. For this, I just took existing geometry from the plane, duplicated it and added it to the edge of the plane, alternating the shape until I was happy with the outcome. 
When the wing was completely, I got all the geometry that was part of the wing and grouped it. Since it's been grouped, it's pivot is automatically been centred to the origin, so all I had to do to mirror it was duplicate and add -1 in the Scale X. 
Now that the model is complete, the next thing to do is clean up the outliner and label every bit of geometry I have. This is good practice as in the industry, after you've modelled something and you pass it on to the next person to look at etc, everything needs to be labelled and grouped so it's easy to understand. I did this for my model, and then grouped everything under one group called "Plane" which is the final model so I can manipulate the entire thing easily. 
In order to make the exhaust pipes at the rear of the engine, I created a polygon pipe, scaled it and added divisions until I was happy. I then selected the faces at the back of the pipe and deleted them.
In order to fill the hole at the back of the pipe, I selected the edges surrounding it and filled it with the "Fill Hole" option. 
Then, by selecting faces, extruding, moving, scaling and shaping, I added more interest to the exhaust . I also used a deformer called Lattice, which allowed me to shape the entire geometry in lower resolution. 
When I was happy with the outcome with the shape, I then positioned it where I wanted it on the rear of the engine and duplicated it. I placed the duplicated geometry to the left and in order for it to be in the same position on the right, I mirrored it by freezing the transformations on the geometry on the left, putting the pivot point in the origin, duplicating and putting -1 to mirror it. 
I realised that the engine was a bit far back, so I scaled it slightly so it wasn't so far in and then positioned the exhausts until I was happy. 
In order to make the rear of the engine a little more interesting, I added some more geometry. I started out with a cube, added a division down the height so I could then select the two faces on the top and extrude them to separate them. I adjusted the shape slightly by moving the CVs around and extruded the faces again to bring the geometry higher. I adjusted the shape of the newly extruded parts to make sure they didn't overlap with existing geometry. I then selected the faces facing the engine and extruded them towards the engine's geometry, adjusting the shape if needed. I also added some more resolution to make the shape seem a bit sharper. 
The next thing to do was to fill out the cockpit area with a bit more detail, with things like a seat and a steering wheel. 
However, before I start making those, I had to create a base to put into the cockpit so you can't see the geometry when you look inside the hole. 
To start, I created a polygon cube and deleted the top face. I then turned off two-sided lighting and reversed the lighting on the cube so the outside was now a black colour and the inside is the normal grey colour. I also reserved the other pieces that turned out black. I then pushed the cube down into the cockpit area and scaled it to the size I wanted. I brought it back up so I could see it and work on it better and added some more resolution to give the cube a better shape when it's smoothed. I then brought it back into the cockpit area, and alternated the shape by moving the CVs around until I was happy with the outcome. 
The next thing to create was the seat. I made another polygon cube and scaled it so it was a long rectangle than a cube. I also added some divisions to the geometry. I then selected all of the faces going down the rectangle, turned off "Keep faces together" option, extruded and scaled them in slightly. I also added some resolution on the sides so the edges wouldn't be so round when it was smoothed. I then added a nonlinear 'bend' to the geometry so I could shape it in a way that wouldn't mess up the geometry. When I was happy with the shape, I put into the cockpit, scaled and positioned it where I wanted until I was happy.  
The next thing to create was the steering wheel. I created another polygon cube, added a division down the middle and 4 along the width. I then duplicated it, moved it to the right a bit and scaled it in so it was thinner. Then, selecting the other object, I went into the faces option, selected the left half and deleted them. I then combined the two objected together. I then selected the faces of the two objects facing each other and bridged them.
In order to create some sort of grip, I took the faces on the edge of the object and extruded them out slightly. I then smoothed out the object, and began to add some resolution in order to make some of the edges less round. After I was happy with the shape, I then mirrored the geometry. Then, I scaled it in and changed the shape slightly by adjusting the CVs. When I was happy with the shape, I scaled it in and positioned it where I wanted it in the cockpit. I then created a NURBs cylinder and placed it behind the steering wheel so it wouldn't look like it's floating in the air. 

Building the fins


In order to add more detail on the plane, I created some fins at the rear end of the plane. 
I started off with a polygon cube and adjusted the shape by simply moving and scaling the CVs around until I was happy with the size and shape of the fin.
I then duplicated that shape and placed it on the side of the plane, angling and scaling until I was happy with it's position. I also needed to make the rear of the plane a bit thicker to hide some of the geometry from the fin that has gone through the main body of the plane. In order to begin this process, I had to delete the history of the NURBs primitive that made up the main body of the plane, and inserted two isoparms at the rear of the plane. Then, in the Hull option, I scaled it in, creating a slightly thicker edge. 
I changed the edges of the rear of the plane slightly by moving the CVs around, and I needed to duplicate and mirror the fins that I made so it's on both sides of the plane, not just one. This was done by selecting the fin sitting on the edge, freezing it's transformation and centring it's pivot to the origin, duplicating it, putting -1 in the X region and then freezing the transformation on the newly duplicated object.  
In order to build the windscreen, I need to extract a curve from the polygon geometry. 
I started by adjusting the shape of the polygon slightly to make it a bit wider, then selected the edges around the polygon and duplicated the surface curve. I then hid the geometry at the back so I could select all of the curves and attach them together. I also deleted the history so I could move it along and adjust it. Furthermore, I had to rebuild the curve so it would be easier to work with.
The next step was to bring back the geometry I had hidden and fit the curve I just made to the shape better, duplicate it, pull the duplicated version further along, scale it up and change the shape by moving the CVs around. 
I then selected both curves and lofted them, resulting in the gap being filled with new geometry. In order to create a rim outside the edge of the windscreen, I selected the curve on the edge of the windscreen, created a NURBs circle and clicked Extrude in order to get a tube like geometry around the rim of the windscreen. Then, with the NURBs circle selected, I scaled it slightly in order to flatten the geometry to make it seem more metallic. 

Building panels


The technique I learnt in this step is to create panels from converted geometry. 
In order to build some panels on the plane, I selected the geometry of the main part of the plane, and converted it to polygons. I then selected half of the polygon geometry in the faces option, and deleted them as later on I am going to make both symmetrical so I only need to work on one side of the plane. 
Still in the faces option,  I selected the faces of the polygon geometry that I wanted to use to create my panels, then pressed shift as I selected the entire plane in order to invert my selection, and deleted the excess geometry, so all I was left with is the faces I selected to create my panels. 
I then extruded the polygon panels in order to make them a bit thicker, and adjusted the shape of them by inserting resolution with the Insert Edge Loop Tool until I was happy with the final outcomes of the shapes.
I needed to add some more geometry around the base of the wing too. I gathered all of the curves I created into one group so they were easier to find, and tried to find the one that was closest to the base of the wing. However, I must have accidentally deleted it some time ago, so I took one of the curves I had shoved to the side for a time like this, duplicated and shaped it to how I wanted near the wing. I then duplicated that curve again and scaled it so it was bigger than the original one. I then shift selected the other curve and lofted them. I then converted that piece of geometry into a polygon, smoothed it and adjusted it's shape by moving the CVs around until I was happy with the outcome. 
To start adding some more detail to the spine, I selected the faces on the spine that sit above the plane, duplicated them and lifted them slightly above the spine. I then adjusted the shape by moving the CVs about.
In the Edges option, I selected the edges of the shape at the bottom and extruded them down, out and to the side. I then adjusted the shapes using the CVs. When I was happy with the positioning, I extruded the whole shape to make it thicker, and inserted some extra resolution to sharpen up some edges. 
I then did exactly the same things to the shape sitting behind it, adjusting and extruding until I was happy with the outcome. 
I also added a bit of detail at the bottom of the plane. I made a NURBS primitive torus, and using the End Sweep, got rid of the top half of the torus. I scaled it in, placed it on the underbelly of the plane and scaled it in until it was like a tube. I then added some more resolution by inserting isoparms and adjusting the shape slightly in the Hull option. I then moved the CVs around into the base of the plane. 

Front spine piece


The next thing to learn to do was use both polygons and NURBs combined, so I created a front spine for the plane. 
The first thing to do was create the shape, so I got a polygon cube, added some divisions and shaped it, scaling and adjusting the CVs in order to get the shape I wanted. 
Then, using the CV Curve Tool, I created a path that I want the shape to follow. After I was happy with the shape of the path, I selected the faces of the shape, shift selected my path and extruded it. The shape then followed the path along the front of the plane. I added some divisions to the geometry and adjusted the Taper option to make it a bit thinner at the end of the geometry. 
I then did the same thing at the bottom of the plane, but this time, I made the path a little more complicated and interesting. Following the same steps as above, I shift selected and extruded, adjusting some CVs to clean up the geometry. I then closed the gap between the two bits of geometry at the top. I made them the same part of an item by selecting both and combined them, deleted the faces where they're going to be bridged, and then selected each CV to it's corresponding CV, so two sitting opposite each other and merged them together. This eventually closed the gap. 
I'm not done adjusting the bridge however. When I smooth the final shape, it curves too much where I've joined the geometry, so in order to make it sharper, I added more resolution using the Insert Edge Loop Tool and it instantly became a sharper edge. 
The spine could do with some more detail, so I selected all of the faces inside the spine and extruded them and pulled them up out of the geometry. I then fixed up any creases by adjusting the CVs and adjusted the shape of the spine at the bottom of the plane. 
I also adjusted the shape at the top of the plane, so the geometry went slightly into the cockpit. I selected the faces and then extruded them. After smoothing, I could see that the shape doesn't fall to the edges of the cockpit, so by adding more resolution with the Insert Edge Loop Tool, the shape was then adjusted to the desired length.
I added a bit more detail by making a crease. By inserting more resolution with the Insert Edge Loop Tool, I selected the faces in-between and extruded them inwards, scaling them slightly. With this the base of the front spine is complete. 
The next thing to do was to create the fan blades, so I started off creating a NURBs cylinder and placing it on top of the nose of the fan. I then altered the shape of it by scaling and going into the Hull option in order to modify the cylinder into a more fan blade shape.
After modifying and creating a shape for the blade that I was happy with, I then needed to make more, but without tediously having to duplicate and place them manually. So I used the Duplicate Special option in order to instantly create more blades. 
Before I could do that though, I had to figure out the angle that I wanted the blade to tilt. It was around -10 in the Rotate Z axis which looked desirable.
The next thing is to figure out how many blades I want. The math was quite simple, as it's going around a 360 degree circle, and diving that by 10 gives us 36. I already have 1 blade out of 36, so I know I only need 35 more blades to go around nose. 
Going into the Duplicate Special option, I entered in -10 for the Y and 35 in the number of copies I want to make. I then applied it and it instantly created all 35 blades and I now have my fan complete.