The De Havilland DH.101 Mosquito Hawk

kitnut617 · February 14, 2011, 09:06:46 AM

As I wanted to procede with what I want to do with the nacelles and props, I dug out my box of projects. One of the projects in it, I had started to make a Sea Fury Mk.X with a four blade prop using a spare Tempest Mk.II cowling which was still loose, so carefully prying the cowling apart I got the spinner off. This set-up has the prop set in the spinner which is then attached to a faceplate which the pin goes through to allow the prop to turn. This faceplate then is glued to the Tempest cowling's face.

This prop/spinner/faceplate assemble is a perfect fit for the DH.101 spinners if the faceplate is used as part of the DH.101 spinner, it matches it spot-on, even the rear diameter of the faceplate is right on the money. The only thing that will be needed to do is to move the front prop further forward in the spinner to allow for the rear prop to fit towards the back end.

Here's a pic of what I mean, on the right is the Tempest Mk.V spinner.

kitnut617 · February 20, 2011, 03:59:27 PM

Rumaging around for suitable opposite turning propellers that look like the Matchbox Tempest prop, I found I had another Tempest Mk.II spinner. So I've started to build one of the nacelles.

Here you can see I've sanded of the exhaust stubs from the Mk.I conversion, I've added a 60 thou' spacer in between the two fuselage halves and glued everything together. I've moved the prop further forward in the spinner and also added 60 thou' card to the rear of the Mk.II spinner. This seems to be just what the drawing shows. The shape of the nacelle is quite close to the drawing now too.

I've ordered two sets of Quickboost Tempest exhaust stubs and also a set of Quickboost P-47 props. I'm not sure if the props are what I'm after but until I see them I can't make a decision about it. There is a couple of other possibilities though, the Aeroclub 1/48 F3F prop blades look about right, as do 1/48 Spitfire Mk.I/II props but trying to find something that looks like the Matchbox Tempest props is getting a bit hard.

R simmie · February 20, 2011, 10:24:00 PM

Hello Kitnut.

looking good....just wondering what kit you got the Tempest Mark II spinner from?
Was it a Matchbox kit?
Also what's 60 thou' roughly in mm for us unfortunate metric folk

R Simmie

kitnut617 · February 21, 2011, 07:02:53 AM

Quote from: R simmie on February 20, 2011, 10:24:00 PM
Hello Kitnut.

looking good....just wondering what kit you got the Tempest Mark II spinner from?
Was it a Matchbox kit?
Also what's 60 thou' roughly in mm for us unfortunate metric folk

R Simmie

Matchbox Mk.II, but it looks like a Sea Fury one would work too. And as I said a few posts back, the front spinner of the 1/48 Seafire Mk.47 works too, that needs a bit of styrene card too.

Fortunately, my vernier has thousands of an inch and mm's, re-measuring the card, it's actually 65 thou' thick, or 1.5mm plus a very tiny little bit. The spinner then measures 13.5mm once the card has been glued on.

kitnut617 · February 24, 2011, 06:53:04 AM

Got a bit done yesterday. I needed to know how much of the Tempest fuselage I will be using, and it looks like there won't be much left of it when I'm done.

I traced out the shape of the nacelle fairing that goes over the wing, I found the tip of it reach as far back as the rear of the Tempest's cockpit opening. So I've packed the interior with some more Milliput and then sanded it down. I've put in much more than I need I think but once this nacelle is finished I'll know what has to be done to the other three.

The opening in the bottom of the Tempest fuselage is nearly bang on for the wheel bay opening so there shouldn't be too much to do there, the tricky bit will be tapering it off to where the nacelle ends. On the prototype DH.101 this finishes just a tad behind the wing trailing edge but I've got a feeling it would have changed. This is because of what I have been reading about the Mosquito and Hornet. Both had a very extended flight testing program to understand the airflow around the nacelles because of the buffeting this caused on the tailplanes. I suspect the DH.101 would have run into similar problems if it started off with the nacelle shape it has on the drawing.

kitnut617 · February 28, 2011, 07:53:56 AM

Using the paper outline of the nacelle, I transfered the shape to the Tempest fuselage, this now sets where the wings start and finish. The next job was to figure out just exactly where the wing chords go in the side view. To do this I had to make a start on the wing spars which revealed that the chords I had developed needed looking at again. I found that for the most part the outer wing chords are constant (that is the same shape but bigger or smaller depending which way you look at it). The last chord at the wingtip (not the actually wingtip but the one on the end of the ailerons) I found was a bit different though. This is because the leading and trailing edges are already curving into the wingtip, so I went back to the next chord position which is on the straight parts of the edges. Doing some doulble checks proved that the chords all through the outer wing are much the same.

The inner wing chords though are another thing altogether, they are different from the fuselage root to the inside of the nacelle. There are three different chord profiles on the DH.98 drawing which shows me what to do (I think ---

) so using the one that is shown against the nacelle I made a paper template and I added the spinner's centerline to it to use as a reference. I did the same for the outer wing chord where it attaches to the nacelle. Then I figured out where the spinner centerline is on the Tempest fuselage and then transfered the chord shapes to it. In the pics below you can see where these shapes are but they may change as I get more and more into the development side of things. This was just to give me an idea what will be involved.

All in all, the most fun so far has been all the working out of the drawings and trying to relate it into hardware.

kitnut617 · March 02, 2011, 09:11:13 AM

The exhaust and P-47 prop that I ordered arrived, these are very nice casting. The blades will need to be shaped a bit to match the Matchbox Tempest props but before I do that, I've some others on order so I'll wait until they get here then make a decision.

kitnut617 · March 16, 2011, 06:46:23 PM

I've had a bit of a rethink on the second DH.101 I'm going to build, I'll work along the lines that the Sabre Mk.VII engine that was bench-tested to 5500 hp was a success and went into production along with the Mk.VIII, the contra-prop version. Having all this extra power would mean something to soak up this power so I'm thinking a contra-prop with two five blade props to it.

I've got an Aeroclub white metal Sea Fury prop in the stash and I've experimented with it, a twist of a blade here and one there and now I've got a five blade prop which would turn in the opposite direction.

I've also being giving some thought to this other DH.101, I'm making it as a dedicated Tallboy bomber. It would fly at extremely high altitude to get the best that Barnes Wallis wanted out of the bomb, so I'll probably give the DH.101 extended wingtips like the DH.98 Mk.XV had. But I've been reading in the Sharp/Bowyer book that in the last few months of the war, PR Mosquitos started to not return from missions in alarming numbers. This after a number of years where they went practically un-interceptable. The book relates some harrowing tales by crews that had survived repeated attacks by the German jets, so I'm thinking that maybe the un-armed feature of the bomber variants of the DH.98 would have had to be changed. I'm thinking of some rear facing remotely operated guns, either in a A-26/B-29 type turret behind the bomb bay, or something really British and go with the barbettes at the ends of the nacelles. Not sure which direction I want to go with it at the moment.

The Wooksta! · March 17, 2011, 02:03:17 AM

A guy my Father knew was crew on Mosquitos and he said that there was one mission where they were repeatedly buzzed by an Me 163.

Extreme altitude - 35-40,000ft - would give the Mosquito immunity, for a time at least. The German jets tended to flame out at altitude.

TsrJoe · November 30, 2022, 03:31:20 AM

Looking good, the 101 is a very different bird indeed from a 'normal' Mosquito.
I have got as far as fuselage and tail unit (wood & styrene) still to create the engines and wings. The only kit part of use seems to be the canopy

I am rather tempted to 3d print an approx 1/60 scale Mosquito for the wings

Best wishes, Joe

The Wooksta! · November 30, 2022, 06:48:38 AM

That being the case, you may as well do the fuselage too, the the jet one seems to be based on the 101, as I found out some time back.

Actually, would the Revell fit the box scale B57 Canberra not be a good fit for the fuselage? Thought about it when I was looking at the fuselage during the planning for my Avro 729.

kitnut617 · November 30, 2022, 06:59:15 AM

Thanks Joe, unfortunately my medical condition has put a stop to just about everything that needs me to use my fingers in 'fine motor control'. I can still grab a handful, but finger use, especially the thumbs and the next two fingers just don't grip anything.

I went through my thread here to see what I have written, here's a couple of things I can clarify now.

The main wheels are almost dead ringers of the Airfix B-25 main wheels in diameter and width. The u/c leg is an enlarge DH Hornet style leg (but not as big as the 1/48 Hornet leg.
I found the fin/rudder of a 1/48 DH Hornet is practically a dead ringer in size and shape to the DH.101 fin/rudder.
The drawings Tony gave me to use now appear in his book 'British Experimental Combat Aircraft of World War II'

kitnut617 · November 30, 2022, 07:02:13 AM

Quote from: The Wooksta! on November 30, 2022, 06:48:38 AMThat being the case, you may as well do the fuselage too, the the jet one seems to be based on the 101, as I found out some time back.

Actually, would the Revell fit the box scale B57 Canberra not be a good fit for the fuselage? Thought about it when I was looking at the fuselage during the planning for my Avro 729.

No Lee, the Canberra fuselage has round cross-section from nose to tail, the DH-101 is more egg shaped with the large end at the bottom. When I scaled the fuselage of the DH.98 to 1/60 scale I found that the bottom profile line matched the DH.101 profile, but what is different is the top profile line doesn't taper like a DH-98, it's straight and level with the datum line, but then just at the rudder hinge line, takes a sharp turn downwards so the end points join up together at a point