Bombers and Agility

[pbehn]

I spent three months just NW of Dhahran, about 9 months over three rotations in Dhahran, and about a month at Prince Sultan. I experienced very little humidity, but did encounter much of the very fine sand (think it's too fine for concrete). However, I'm a Floridian so humidity in the 30-50% range will feel low.

As for special treatments I know of none. The Saudi Eagles would be put on "alert" for a month or more at a time, and not turn a wheel. Then they would fly and return with no write ups. UFB. At Eglin and JAX long weekends would see a a larger than normal amount of write ups after the first sorties (the more they fly the better).

In the US we would do a bird bath upon returning if we got below 3k over the Gulf / ocean (pilot activated taxi through wash or fire trucks). Kadena started the bird bath trend I believe after encountering unexpected corrosion.

Cheers,
Biff

Obviously the weather changes throughout the year and throughout the day. I used to pass Dhahran airport every day going to work at a factory in the desert.
In June July they stopped work around sunset because the air temperature was above body temperature and the humidity shot up above 90%, even the Japanese and Filipinos who were used to high temperarures and humidity couldnt stand it on night shift. Below are the extremes, 5% on 6th June 94% on 2 June. 26C to 47C on 2 June.

High & Low Weather Summary for June 2020

	Temperature	Humidity	Pressure
High	47 °C (2 Jun, 13:00)	94% (2 Jun, 05:00)	1005 mbar (2 Jun, 05:00)
Low	26 °C (2 Jun, 04:00)	5% (6 Jun, 13:00)	993 mbar (29 Jun, 03:00)

 

[swampyankee]

u

Obviously the weather changes throughout the year and throughout the day. I used to pass Dhahran airport every day going to work at a factory in the desert.
In June July they stopped work around sunset because the air temperature was above body temperature and the humidity shot up above 90%, even the Japanese and Filipinos who were used to high temperarures and humidity couldnt stand it on night shift. Below are the extremes, 5% on 6th June 94% on 2 June. 26C to 47C on 2 June.

High & Low Weather Summary for June 2020

	Temperature	Humidity	Pressure
High	47 °C (2 Jun, 13:00)	94% (2 Jun, 05:00)	1005 mbar (2 Jun, 05:00)
Low	26 °C (2 Jun, 04:00)	5% (6 Jun, 13:00)	993 mbar (29 Jun, 03:00)

When a college friend was serving in that part of the world (in 1979 - 1980), he reported that the water temperature got high enough to affect the performance of the ships' steam engines. He also told a story about the Glover getting renumbered from AGFF-1 to FF-1098 leaving its Soviet shadowers very confused for a couple of days)

 

[BiffF15]

Obviously the weather changes throughout the year and throughout the day. I used to pass Dhahran airport every day going to work at a factory in the desert.
In June July they stopped work around sunset because the air temperature was above body temperature and the humidity shot up above 90%, even the Japanese and Filipinos who were used to high temperarures and humidity couldnt stand it on night shift. Below are the extremes, 5% on 6th June 94% on 2 June. 26C to 47C on 2 June.

High & Low Weather Summary for June 2020

	Temperature	Humidity	Pressure
High	47 °C (2 Jun, 13:00)	94% (2 Jun, 05:00)	1005 mbar (2 Jun, 05:00)
Low	26 °C (2 Jun, 04:00)	5% (6 Jun, 13:00)	993 mbar (29 Jun, 03:00)

All of my visits save the first were in the heat of the summer (lowest humidity). I had several friends who taught at the Saudi Weapons School (were there for a year) and their comments about the jets flying well mirrored my experience.

If you took an Eagle from high heat to cold temps (one location to the next), or vice versa, don't refuel it until it's ready to fly or your ramp will be covered in JP-4. Plus hydraulic leaks. They fixed that problem on the F-18.

Cheers,
Biff

 

[Shortround6]

Getting back the maneuverability or agility of bombers we have instantaneous maneuver and sustained maneuver. The latter has a lot to do with available power/thrust.

According to one website not only does the stall speed go up 20% in a 45 degree bank but the drag goes up 100% while in a 60 degree bank the stall sped goes up 40% but the drag goes up 300%. a 45 degree bank is a 1.4 G turn and a 60 degree bank is a 2.0 G turn. Harder turns get worse a lot quickly.

A low power to weight ratio bomber may very well be able to bank and turn at a steep angle for a short period of time but it is going to be a very short period of time. The pilot is going to have to time his turns carefully to throw of the attacking fighters aim or cause it to over shoot and then straighten out to pick up speed for the next turn/avoidance maneuver while the fighter/s circle around for another attack.
Many early British bombers suffered from the two pitch props as at low altitude and less than full speed the prop/s had the wrong pitch and would not allow good use to be made of full throttle power settings, most efficient use of the props was at less than full rpm/power which really hurt climb/turn by limiting thrust.

 

[WARSPITER]

Getting back the maneuverability or agility of bombers we have instantaneous maneuver and sustained maneuver. The latter has a lot to do with available power/thrust.

According to one website not only does the stall speed go up 20% in a 45 degree bank but the drag goes up 100% while in a 60 degree bank the stall sped goes up 40% but the drag goes up 300%. a 45 degree bank is a 1.4 G turn and a 60 degree bank is a 2.0 G turn. Harder turns get worse a lot quickly.

A low power to weight ratio bomber may very well be able to bank and turn at a steep angle for a short period of time but it is going to be a very short period of time. The pilot is going to have to time his turns carefully to throw of the attacking fighters aim or cause it to over shoot and then straighten out to pick up speed for the next turn/avoidance maneuver while the fighter/s circle around for another attack.
Many early British bombers suffered from the two pitch props as at low altitude and less than full speed the prop/s had the wrong pitch and would not allow good use to be made of full throttle power settings, most efficient use of the props was at less than full rpm/power which really hurt climb/turn by limiting thrust.

I was right with you up until "According to one website"........

 

[FLYBOYJ]

I was right with you up until "According to one website"........

Actually if you go to any "flying 101" manual, website or whatever, that's a rule of thumb. Here is "one" website:

https://www.aopa.org/news-and-media/all-news/1999/january/flight-training-magazine/one-good-turn#:~:text=In%20a%2045%2Ddegree%20bank,airplane's%20wings%2Dlevel%20stall%20speed.

 

[WARSPITER]

Right thanks ... so if the degree of angle is not that which can be angled in under 20 degrees C then the gliders tow rope will snap
leaving the angle of attack at a loss which then means that conversion to a jpeg for low file size posting becomes impossible which
then leads to a lost angle of PI to the third times nine - ie LA = P39 - which converts to a lost angle of attack due to a change in the
centre of gravity....... I think.

 

[FLYBOYJ]

Right thanks ... so if the degree of angle is not that which can be angled in under 20 degrees C then the gliders tow rope will snap
leaving the angle of attack at a loss which then means that conversion to a jpeg for low file size posting becomes impossible which
then leads to a lost angle of PI to the third times nine - ie LA = P39 - which converts to a lost angle of attack due to a change in the
centre of gravity....... I think.

I don't know what this has to do with C/C or gliders, this is known physics based on bank angle, I think you're overthinking this. Now with regards to a tow line breaking because of load, that is determined by either rope strength and/ or weak link installation against the load being pulled.

 

[WARSPITER]

Thanks again. I suppose I will pick it up as I go along.

 

[JDCAVE]

Getting back the maneuverability or agility of bombers we have instantaneous maneuver and sustained maneuver. The latter has a lot to do with available power/thrust.

According to one website not only does the stall speed go up 20% in a 45 degree bank but the drag goes up 100% while in a 60 degree bank the stall sped goes up 40% but the drag goes up 300%. a 45 degree bank is a 1.4 G turn and a 60 degree bank is a 2.0 G turn. Harder turns get worse a lot quickly.

A low power to weight ratio bomber may very well be able to bank and turn at a steep angle for a short period of time but it is going to be a very short period of time. The pilot is going to have to time his turns carefully to throw of the attacking fighters aim or cause it to over shoot and then straighten out to pick up speed for the next turn/avoidance maneuver while the fighter/s circle around for another attack.
Many early British bombers suffered from the two pitch props as at low altitude and less than full speed the prop/s had the wrong pitch and would not allow good use to be made of full throttle power settings, most efficient use of the props was at less than full rpm/power which really hurt climb/turn by limiting thrust.

I found this document in W/C Hagerman's logbook (419 Squadron). Hagerman was also an instructor at 1662 Conversion Unit, so would have taught the manoeuvre on Heavy Bombers. Note: ASI refers to "Air Speed Indicator" and was calibrated in MPH, rather than knots. ASI's in knots were a late war development and some squadrons had not yet converted over until war's end.

 

[ThomasP]

Hey Darthtabby ,

I do not know if this will help answer your questions? It is a post-war summary of several war-time reports and one post-war report where, velocity and g recorders were fitted to a number of aircraft while in operational use. The test sample is a bit small but there are some interesting bits.

 

[SaparotRob]

Yes they were in Lancasters. Probably not but if you are told to fly at 60ft in the dark towards a flak tower and other stuff you are unlikely to care about such instructions. I remember some test pilot doing a barrel roll in a Boeing 707, Boeing were horrified although the pilot explained that he maintained just 1 G. While Boeing agreed, it just isnt what potential passengers want to see so he never did it again.

The main objective to the practicing was for all the crew to know what would happen. What could get thrown about that you needed and so had to be secured, What you could hit your head arms and ribs on etc. What you could hold on to so you reached for it without thinking. As far as I remember the favourite was a rapid climb with engines partially shut down then engines on full power for a dive and turn to left or right starting the "corkscrew".

Some crews never spotted an enemy fighter, but it was a possibility as soon as you crossed the coast, its best for all if they train for it.

Wouldn't flying at 60ft in the dark towards a flak tower and other stuff void the manufacturers warranty anyway?

 

[swampyankee]

Wouldn't flying at 60ft in the dark towards a flak tower and other stuff void the manufacturers warranty anyway?

Being in combat would not only void the warranty but none of the damage would covered by your airframe insurance.

 

[SaparotRob]

There's always catch.

 

[wjkuleck]

Since you mentioned the B-36, which I worked on and flew in occasionally for over 5 years, I will repeat what I was told then: prior to air-to-air missiles but after the general use of jet fighters, the Peacemaker was presumed to be pretty safe at 40,000 ft. If the B-36 was flying at anything close to top speed, the only reasonable approach was from the rear. The big wing made it possible for the B-36 to turn so much tighter that the pursuer would be a mile or two away before completing its turn. Few fighters of that era (early to mid 50s) could reach that altitude with enough fuel to engage in a protracted dogfight. An F-89 pilot once said he could have gotten to a high-flying B-36, but he would have had to walk home.

The Navy maintained that the F2H-2 could successfully intercept the B-36. It is alleged that a Phantom did indeed, albeit unofficially, get in position to kill a Peacekeeper.

McDonnell F2D-1/F2H-1 Banshee

 

[wjkuleck]

Kevlar and Spectra are organic compounds; so are the vast majority of composite matrices. None of these are natural, but hemp, sisal, and cotton fiber are being used as reinforcement fibers in secondary structure by several car companies.

If I recall from what I've read, wooden primary structure was strongly discouraged by the CAA after some airliner crashes in the late 1920s/early 1930s, so none of the companies that specialized in building large aircraft had any current expertise in manufacture of wooden structures.

You've reminded me of the C7 Corvette's balsa sandwich floor.