Hawker Typhoon: With 20/20 hindsight

[stona]

Yep it was.

In what sense was the rear fuselage failure a serious problem for operational aircraft? It was discovered at an early stage that a combination of factors were causing the failure at the transport joint (IIRC) and the problem was addressed. That would be why so few operational losses were attributed to this.

The Typhoon was far from a disaster, it was the best ground attack aircraft the RAF had in 1944/45, at exactly the time they needed one. Happy coincidence given the RAF's resistance to the CAS role? Maybe, but it's a good job it had the Typhoon. The alternative, in this time frame, was the Spitfire which even its most ardent advocates would not claim to be a great fighter bomber.

Cheers

Steve

 

[stona]

Double post

 

[fastmongrel]

I suppose with complete 20/20 hindsight it would look like this

 

[tomo pauk]

Or maybe the Hunter-alike?

 

[wuzak]

I suppose the Typhoon was a failure in that it failed to do what it was designed to - that is, replace the Spitfire.

But the fact that it became a more than useful aircraft would suggest that it was not a failure or disaster.

 

[Glider]

The Typhoon wasn't a disaster. It was an exceptional GA aircraft at a time when the RAF didn't have a GA aircraft. In air to air combat it held its own at low to medium altitude and was much faster than a Spit or practically anything else at low to medium altitude.

Half the reason the Hurricane pilots suffered heavy losses was because they were being used as fighters well past its time or as a GA aircraft for which it lacked almost everything, range, payload and performance, you name it. Or the totally unreasonable delay in using Spits overseas in the mid and far east. None of which is the fault of Hawkers.

Was it perfect, no it wasn't, was the Tempest a better aircraft, yes it was. Would it have been better with a low flow laminar wing, yes, but how many aircraft in the world were being designed using such a wing in 1939 and the answer is none. So to look back in hindsight and its easy to be critical but at the time in 1939 when the decisions were made and it was a good one.

As to the original question I would have liked to see them in the Far East. The Japanese in 1943 didn't have anything that came close to catching the Typhoon and the pilots knowing that it couldn't turn well were far less likely to try and take on the Japanese in a turning combat. Spitfire and Hurricane pilots tended to try this as in Europe they had aircraft that could turn inside the Luftwaffe, but against the Japanese they came severely unstuck.

 

[tomo pauk]

...

Was it perfect, no it wasn't, was the Tempest a better aircraft, yes it was. Would it have been better with a low flow laminar wing, yes, but how many aircraft in the world were being designed using such a wing in 1939 and the answer is none. So to look back in hindsight and its easy to be critical but at the time in 1939 when the decisions were made and it was a good one.
...

Agreed with what you say, but the quoted part. Nobody here is proposing the laminar flow wing for such an early A/C. However, nobody in the late 1930s was designing the fighter around a wing that have had 19% thickness to chord (at root) ratio. The Spitfire was at 13.2%, Bf-109 was at 14 (14.2?) %, the Fw-190 at 15.3%, Soviet fighters were at 15% etc. So the people at Hawker were completely 'allowed' to go for, say, NACA 230 series 15 to 15.5% thick wing, like Fw did for the 190, or what Soviets did for the LaGG3*.
Or, do what Supermarine did for Spitfire - go for the NACA 2200 series profile, even if it is 15% thick, opt for a 300 sq ft wing (instead of 275 sq ft) and have themselves a performer. Even the granpa Clark YH was't that a draggy thing in the MiG-1/3, since it was thin.
Unfortunately, Hawker believed to the other folks (RAE folks?) that 19% wing is great.

*Now that we're at it, please make space in front of the front spar and retract the U/C there - should give plenty of space between spars.

 

[gjs238]

For all the trouble, the Brits may have been better off license-building Vought F4U's and Pratt Whitney R-2800 Double Wasp's.
Or trying to ensure adequate production to fulfill their needs in the US.

 

[tomo pauk]

Merlin Mustang fits the needs far better, and it is cheaper both to purchase and operate. The British (and the US) ensured that Merlins are produced in the USA, for both countries.

 

[Glider]

For all the trouble, the Brits may have been better off license-building Vought F4U's and Pratt Whitney R-2800 Double Wasp's.
Or trying to ensure adequate production to fulfill their needs in the US.

Unfortunately the F4U was about two years too late for the RAF, was slower in both climb and speed than the Typhoon at low level, so when the RAF needed it the F4U wasn't a contender. Note these are compared to the F4U1.

 

[Shortround6]

First batch of 250 Typhoons delivered September 1941 and June 1942.
2nd batch of 250 Typhoons delivered June 1942 and September 1942.
3rd batch of 700 Typhoons delivered September 20th 1942 and May 5th 1943.
4th Batch of 600 Typhoons delivered April 5th 1943 and December 7th 1943.

May 1943 sees first production Merlin Mustang and Dec 1st 1943 sees first fighter sweep of Merlin Mustangs From England.

Production of F4Us only catches and exceeds Typhoons in the last few months of 1943. Only 178 F4Us were built in 1942.

 

[Juha]

I suppose with complete 20/20 hindsight it would look like this
IMHO a real beauty and very nice plane to fly, at least from F.2 onwards according to Eric Brown.

Juha

 

[Juha]

...Unfortunately, Hawker believed to the other folks (RAE folks?) that 19% wing is great...

RAE got it sometimes badly wrong, another case that springs into my mind was when they strongly recommended T-tail for P.1 (later developed to Lightning) but fortunately Petter kept his mind and P.1 got its lowplaced horizontal tail.

 

[pbehn]

Was tail failure really that big of a problem? Going thru the Typhoon lost list there is only a few and that was early.

from The Hawker Typhoon, Tempest, Sea Fury

RAF pilots found the aircraft fast and powerful at low altitudes, but it suffered from slow rate of climb and poor high altitude performance. In fact, the Tiffy had more than its share of teething problems. Cockpit visibility was bad; controls were heavy; low speed handling was poor; the Sabre engine tended to catch fire on start-up, and had to be overhauled every 25 flight hours in any case; there were carbon monoxide leaks into the cockpit that required continuous use of oxygen; and the tail section showed a distressing tendency to fall off.

Several test pilots were killed in the Typhoon. Of the first 142 delivered, only seven were not involved in serious non-combat accidents due to engine or airframe failures at one time or another. The tail problems turned out to be due to elevator flutter and were cured by modifying elevator balance, but that didn't happen until very near to the end of the war. Since nobody knew what was causing the trouble before that time, a distinctive row of "fish plates" was attached in a ring around the fuselage just ahead of the tailplane as an interim measure to keep the tail on.

* Unsurprisingly, the Air Staff and Ministry of Aircraft Production wanted to kill the Typhoon. The aircraft was given a reprieve in late 1941 when Luftwaffe Focke-Wulf FW-190 fighter-bombers started making fast low-level "hit and run" attacks in ones and twos on British coastal installations and strategic targets. The Typhoon was the only RAF fighter fast enough to catch the raiders.

The Typhoon's prospects for survival improved in 1942, when it became obvious that the Tiffy's rugged airframe, powerful engine, and heavy armament made it an excellent fighter-bomber. The leading advocate for the type was one of the aircraft's pilots, Roland P. "Bea" Beamont, who flew low-level attack missions to demonstrate the Typhoon's virtues as a strike aircraft, and was energetic in its defense. The Typhoon was evaluated with drop tanks, two 450 kilogram (1,000 pound) bombs, and racks for eight 27 kilogram ("60 pounder") rocket projectiles ("RPs"). Interestingly, during trials a Typhoon firing RPs with inert warheads had them bounce up and punch through the wings of the aircraft in front. Though the pilot was undoubtedly startled, the rockets did no serious damage to his aircraft.




I dont know about Sidney Camm having political influence, the Typhoon was close to being cancelled a few times. When he made the Tempest he said he had to make something that resembled a Spitfire or the AM wouldnt buy it.

 

[Aozora]

from The Hawker Typhoon, Tempest, Sea Fury
Several test pilots were killed in the Typhoon. Of the first 142 delivered, only seven were not involved in serious non-combat accidents due to engine or airframe failures at one time or another.

There doesn't seem to be any primary source material to back up this claim, so, as with many such internet sources, this can be taken with a large dose of salt. The best source of information on the Typhoon/Tempest family is Chris Thomas - if none of his books have been consulted chances are errors will have crept in.

The tail problems turned out to be due to elevator flutter and were cured by modifying elevator balance, but that didn't happen until very near to the end of the war.

This is very wrong; the elevator mass balance was modified starting September/October 1943, which largely eliminated the problem.

 

[pbehn]

There doesn't seem to be any primary source material to back up this claim, so, as with many such internet sources, this can be taken with a large dose of salt. The best source of information on the Typhoon/Tempest family is Chris Thomas - if none of his books have been consulted chances are errors will have crept in.
This is very wrong; the elevator mass balance was modified starting September/October 1943, which largely eliminated the problem.

sources were at the end
THE HAWKER TYPHOON by Francis K. Mason, Profile Publications, 1966.

FIGHTERS OF WORLD WAR II by Charles W. Cain and Mike Jerram, Profile Publications, 1979.

FIGHTERS OF WORLD WAR II by David Donald, Metro Books, 1998. This document is basically an outline of the chapters on the Typhoon, Tempest, and Sea Fury in this book, with additions from the other sources.

BRITISH WAR PLANES OF WORLD WAR II, edited by Daniel Marsh, Airtime Publications, 1998.

I seem to remember reading that the tail problem also involved the rear wheel and engine/harmonic vibration not exclusively elevator flutter. The Typhoon had an annoying high pitched vibration which didnt go until they fitted a 4 blade prop which was towards the end of the war.

found this in wiki

A major problem, afflicting early production Typhoons in particular, was a series of structural failures leading to loss of the entire tail sections of some aircraft, mainly during high-speed dives. Eventually a combination of factors was identified, including harmonic vibration, which could quickly lead to metal fatigue, and a weak transport joint just forward of the horizontal tail unit. The loss of the tailplane of R7692 (having only 11 hours of flight recorded) on 11 August 1942, in the hands of an experienced test pilot (Seth-Smith), caused a major reassessment which concluded that the failure of the bracket holding the elevator mass balance bell crank linkage had allowed unrestrained flutter which led to structural failure of the fuselage at the transport joint.
Starting in September 1942, a steel strap was fitted internally across the rear fuselage transport joint, although this was soon superseded by Mod 286 (modification number 286), in which 20 alloy "fishplates" were riveted externally across the rear fuselage transport joint, while internally some of the rear fuselage frames were strengthened. This was a permanent measure designed to stop in-flight rear fuselage structural failures and was introduced on the production line from the 820th production aircraft; between December 1942 and March 1943, all Typhoons without Mod 286 were taken out of service and modified. Modified balance weight assemblies were fitted from May 1943. Finally the entire unit was completely replaced with a redesigned assembly from August 1944.[53]
Although these modifications reduced the numbers of Typhoons being lost due to tail assembly failure, towards the end of the Typhoon's life there were more tail failures, this time caused by a change to the undercarriage latch mechanism in late 1944; in high-speed flight the undercarriage fairings were pulled into the slipstream, creating an uneven airflow over the elevators and rudder resulting in tailplane and then rear fuselage structural failure.[53] In total 25 aircraft were lost and 23 pilots killed due to tail failures.[53] Thomas and Shores 1988, p. 20.

 

[Aozora]

sources were at the end
THE HAWKER TYPHOON by Francis K. Mason, Profile Publications, 1966.

FIGHTERS OF WORLD WAR II by Charles W. Cain and Mike Jerram, Profile Publications, 1979.

FIGHTERS OF WORLD WAR II by David Donald, Metro Books, 1998. This document is basically an outline of the chapters on the Typhoon, Tempest, and Sea Fury in this book, with additions from the other sources.

BRITISH WAR PLANES OF WORLD WAR II, edited by Daniel Marsh, Airtime Publications, 1998.

Exactly my point, no primary source documents used, so no way of x-checking whether the statistics quoted hold water.

I seem to remember reading that the tail problem also involved the rear wheel and engine/harmonic vibration not exclusively elevator flutter. The Typhoon had an annoying high pitched vibration which didnt go until they fitted a 4 blade prop which was towards the end of the war.

Four-bladed propellers started being fitted in early 1944, although there were some hold-ups:

From Wiki:

After tests conducted in 1943, it was determined that the Typhoon was capable of carrying a 1,000 lb (454 kg) bomb under each wing. With the increased load, it was decided that the extra take-off performance conferred by a four-bladed propeller was an advantage; this led to the adoption of a four-blade propeller unit (de Havilland or Rotol) from early 1944. Coinciding with the new propeller, it was also decided that the larger tailplanes of the Hawker Tempest were to be fitted when tests showed that larger tailplanes improved the handling characteristics of the Typhoon when carrying 1,000-lb (454 kg) bombs.[57][63] There were, however, problems experienced with oil seal leaks from the new propeller unit as a consequence of which a growing number of Typhoons were held in Maintenance Units (MUs) awaiting the arrival of new seals from the U.S. In addition, some 200 Typhoons were manufactured with the new Tempest tailplanes and the three bladed propeller. A modification programme was inaugurated but it took several months before a majority of operational Typhoons had both the four-bladed propeller and enlarged tailplane.[64][nb 13]

found this in wiki
Starting in September 1942, a steel strap was fitted internally across the rear fuselage transport joint, although this was soon superseded by Mod 286 (modification number 286), in which 20 alloy "fishplates" were riveted externally across the rear fuselage transport joint, while internally some of the rear fuselage frames were strengthened. This was a permanent measure designed to stop in-flight rear fuselage structural failures and was introduced on the production line from the 820th production aircraft; between December 1942 and March 1943, all Typhoons without Mod 286 were taken out of service and modified. Modified balance weight assemblies were fitted from May 1943. Finally the entire unit was completely replaced with a redesigned assembly from August 1944.[53]
Although these modifications reduced the numbers of Typhoons being lost due to tail assembly failure, towards the end of the Typhoon's life there were more tail failures, this time caused by a change to the undercarriage latch mechanism in late 1944; in high-speed flight the undercarriage fairings were pulled into the slipstream, creating an uneven airflow over the elevators and rudder resulting in tailplane and then rear fuselage structural failure.[53] In total 25 aircraft were lost and 23 pilots killed due to tail failures.[53] Thomas and Shores 1988, p. 20.

I stand corrected; the new balance weights were fitted starting in May 1943, not September/October. The source used was Chris Thomas Christopher Shores The Typhoon and Tempest Story - still probably the best book available on the subject, although Chris Thomas has since written others.

 

[pbehn]

Exactly my point, no primary source documents used, so no way of x-checking whether the statistics quoted hold water.



Four-bladed propellers started being fitted in early 1944, although there were some hold-ups:

From Wiki:




I stand corrected; the new balance weights were fitted starting in May 1943, not September/October. The source used was Chris Thomas Christopher Shores The Typhoon and Tempest Story - still probably the best book available on the subject, although Chris Thomas has since written others.

Hey friend we are sharing information here not scoring brownie points over events when my father was a young man. I seem to remember something about harmonics and the wheel rotation leading to the brake being applied after take off ( maybe completely mistaken) On another thread there is talk of harmonics causing problems on the Bf109 if something is prone to resonate then almost anything can trigger it. The elevators would (I think) be the worst but not the only source.


What I posted was a "potted history" but not really wide of the mark.

Cheers friend

 

[Aozora]

Hey friend we are sharing information here not scoring brownie points over events when my father was a young man.

Sorry that you've taken it that way; I am simply pointing out to be wary of information that comes off the internet, plus I'm giving a more accurate timescale for the modifications that were carried out to correct the various problems you are highlighting. That's what's being discussed in this thread, or am I mistaken about that?

 

[pbehn]

Sorry that you've taken it that way; I am simply pointing out to be wary of information that comes off the internet, plus I'm giving a more accurate timescale for the modifications that were carried out to correct the various problems you are highlighting. That's what's being discussed in this thread, or am I mistaken about that?

Since the problem was in part harmonics then almost anything can trigger it, what I posted was a sort of potted history. Sure the imbalance on the elevators would bring it about quickly but other sources could also cause the same effect. All is cool with m Aozora, I have no books here so internet is all I can quote. I am sure I read it could also be triggered by rear wheel rotation so the brake was applied (but maybe I had too many beers) maybe someone can help.

Cheers