Question - Speed differential between the Lanc and the night fighters

[syscom3]

What was the speed differential between a fully Loaded Lanc (typical load out for bombs) and the JU-88 and ME-110, both fully loaded with ammo and fuel. I know the altitude has a lot to do with the speed of all the aircraft, so let's say the Lanc is at 20,000 ft. Let's also say it's summer 1944 so what ever variants were available in those months.

I don't need absolute numbers, just a relative speed rate.

I'm not well versed in this part of the air war (and the aircraft that fought it), which I why I am asking.

 

[davebender]

Loaded British and U.S. heavy bombers (not counting B-29) typically cruised at speeds under 200 mph. Any German night fighter could achieve over 300 mph in level flight. The late war Ju-88G could achieve over 350mph in level flight even fully loaded with radar equipment and flame dampeners.

 

[Rivet]

For an interesting speed differential you might want to compare the Heinkel 219 speed range to the already mentioned 200 mph formation cruise speed of the Lancaster heavy bomber. Wikipedia, or a perusal of William Green's texts on German aircraft, will give you what occured on occasion when one of the fastest night fighters built made a lasting impression on some of her prey in a manner unintended. Regards

 

[syscom3]

I guess my next question would be "did the Lancs go in at cruise speed or at a faster setting?"?

 

[vanir]

Intercepts in general can have massive speed disadvantages, the role of ground directors is to plot intercept courses which take advantageous use of weather and the bomber (suspected) route. This would be also why RAF tactics like false strikes and bomber feints to conceal the true mission were so effective.

What you're talking about is the final stage of intercept, the dogfight. Yes a night fighter will always out dogfight a Lanc or any heavy bomber, every time. They basically use the same engines.
But the difficulties of intercept are well before you're on the enemy's flight path in close pursuit. It's getting there. And with wind speed, different approach directions, unpredictable bomber waypoints, you could be chasing a bomber stream with 300mph airspeed relative to you.
They may have to call a coastal squadron to get them on the way out.

 

[Rivet]

In answer to your post #4, this from a Canadian site: "The average operational - cruising speed, with bomb-load, of the Lanc at 15,000 feet was about 180 m.p.h. I.A.S.; for the Halifax, it was a little better. However, above 18,000 feet the Lanc had the edge. The Lanc also over-took the Hally in rate of climb at about 18,000 feet. its operational ceiling was from 22,000 to 24,000 feet, depending on the aircraft and the pilot. The Halifax's ceiling was slightly less, and the Stirling was left far below at around 15,000 feet. The average operational cruising speed of the Fortress was in the neighbourhood of 160 miles per hour I.A.S. and the Liberator was slightly slower, but both these machines did most of their bombing at close to 30,000 feet, almost 10,000 feet higher than the two British aircraft." Regards

 

[davebender]

I don't think that applies at night.

Luftwaffe ground control attempted to insert night fighters into the RAF bomber stream. Once in the bomber stream it was up to the night fighter crew to find and destroy bombers on their own initiative. Typically such combats were at point blank range and were over before the bomber even knew it was under attack. Multiple kills in quick succession were common before the night fighter ran low on fuel and ammunition. Finding the bomber stream was the most difficult part of the night fighter mission. Like looking for a needle in a haystack in the dark. Only a fraction of the night fighter force accomplished this task on any given night.

Very different from attacking B-17s during the daytime. Day bombers were relatively easy to find. However defensive gun turrets typically saw the German interceptors in time to fight back. Day bombers also had fighter escort.

 

[tomo pauk]

Chart for Lancaster (2 variants); we need German ones to answer the question

 

[fastmongrel]

Doesnt cruising speed vary with the load carried and the range of the mission.

 

[syscom3]

Since the Lancs did not go in formation while on a mission, they had to have a throttle setting somewhat higher than cruise, yet lower than combat speed (which would have sucked up the gas at a high rate). Is that true?

 

[davebender]

That looks like maximum sustained cruising speed. Not the economical cruise speed normally employed on a bombing mission.

 

[Shortround6]

It has been said that Bomber Command losses could have been cut by instructing the crews ( and perhaps adjusting bomb loads) to fly at closer to maximum LEAN cruise settings. This is still less than max cruise settings but would offer a useful improvement in speed over max range or most economical cruise speeds without cutting into the range any where near like going into the RICH mixture cruise settings would.

 

[davebender]

That defeats the purpose of WWII night bombing.

Accuracy was good enough only to aim at an entire city and even then it wasn't unusual to miss. The only way to compensate for such inaccuracy was to drop as much bomb tonnage as possible and hope that a few percent hit something useful.

 

[vanir]

It has been said that Bomber Command losses could have been cut by instructing the crews ( and perhaps adjusting bomb loads) to fly at closer to maximum LEAN cruise settings. This is still less than max cruise settings but would offer a useful improvement in speed over max range or most economical cruise speeds without cutting into the range any where near like going into the RICH mixture cruise settings would.

I was just talking about a Ministry report which mentioned this, in another thread. I believe it was due to them getting lost, rather than lacking the fuel to do the mission. It was so common for whole squadrons to become lost over water at night, that Harris worked it into his mission schedule (his big reform from his predecessor, who scrubbed missions in bad weather as a response and drew the ire of Churchill so was sacked).
To be fair the guy before Harris did lose an entire bomber formation once. The whole thing disappeared like Flight 19. Bad weather, blown off course and probably crashed out of fuel somewhere near Norway iirc.

 

[Siegfried]

Speed realy was a problem for the Nachjagt. Windows drops and feints (spoof raids) would often draw of much of the night fighters to the wrong area: then when the ruse was discovered they had only a small speed advantage to intercept.

Eg if a bomber is cruising at 220mph and the fighter is going full speed at 300mph a tail chase is going to cover 220 miles just to close 80 miles.

Gebbard Adders's history of the German night fighter force also notes that Lancaster cruising speed improved due to improving engines and caused some problems at times although much of this was used up increasing bomb loads it did increase egress speed.

The Germans did develop a coherant pulse doppler system Wurzlaus (improved dramtically as tastlaus and k-laus) that might have helped
disinguish these ruse's somewhat but it all depends on the electronic war.

 

[Tangopilot89]

According to a documentary I watched on the Lanc, its top speed fully bombed up and fuelled was around 275mph and the German night-fighters used were Me110 or Ju88C's.

The Luftwaffe had radar-equipped night-fighters codename 'Wild Boar,' and 'Tame Boar' usually directed in by other means of radar. I would estimate top speeds of between 300-350mph, but the radar would certainly help to vector them in for an attack via the shortest route. Hope this helps in some way.