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 oldbutnotwise       3/16/2013 5:23:27 PM Shooter I just thought of another one   If the B17 bay was so big why did you have to remove the shackles holding 2000lbs BEFORE releasing any bombs stored above them?   oh a 1 B17 mission carrying more than 1000lbs of ANY distance

45-Shooter       3/17/2013 12:46:50 PM

why did the recommended bomb drop sequence state nose to tail, this means that the final row of 3x 1000lbs were still attached when the row before was dropped, yet you claim that 1000lbs was enough to make the aircraft uncontrollable
I did not know this. I always thought it would be one from the back, one from the front, or Vice Verse untill they got to the centeral row of racks? But given the interval between the first and last bomb exiting the plane, it is easy to see why they do not have a problem with stability for that fraction of a second when the last bomb(s) is/are still on the hook, if it was the way you state.

finally can you provide evidence of your statements as you seem to be the ONLY source of this information
OK, here we go again. I used the Range of CG limits as posted many times by others here as the starting point. Then I did a simple moment arm calc to see how far out of range the plane would be IF a 1000 pound bomb hung up in the last row. Since the results are very far out of permitted range, I concluded that what all the current pilot's manuals say about those sorts of things are true. See this;
The center of gravity (CG) of an aircraft is the point at which the aircraft would balance if it were possible to suspend it at that point. It is the theoretical point at which the entire weight of the aircraft is assumed to be concentrated.[1] Its position is calculated after supporting the aircraft on at least two sets of weighing scales or load cells, and noting the weight shown on each set of scales or load cell. The center of gravity affects the stability of the aircraft. To ensure the aircraft is safe to fly, the center of gravity must fall within specified limits established by the aircraft manufacturer.
Back in the early days of flight, in the 20s-30s- and yes the 40s, they did not know nearly as much as they did in say 1946 because they did more research between 1940 and 1945 than in all the prior years combined.
Incorrect weight and balance in fixed-wing aircraft

When the center of gravity or weight of an aircraft is outside the acceptable range, the aircraft may not be able to sustain flight, or it may be impossible to maintain the aircraft in level flight in some or all circumstances. Placing the CG or weight of an aircraft outside the allowed range can lead to an unavoidable crash of the aircraft.

###  Center of gravity out of range

When the fore-aft center of gravity is out of range, the aircraft may pitch uncontrollably down or up, and this tendency may exceed the control authority available to the pilot, causing a loss of control. The excessive pitch may be apparent in all phases of flight, or only during certain phases, such as take-off or descent. Because the burning of fuel gradually produces a loss of weight and possibly a shift in the center of gravity, it is possible for an aircraft to take off with the center of gravity in a position that allows full control, and yet later develop an imbalance that exceeds control authority. Calculations of center of gravity must take this into account (often part of this is calculated in advance by the manufacturer and incorporated into CG limits).

###  Weight out of range

Few aircraft impose a minimum weight for flight (although a minimum pilot weight is often specified), but all impose a maximum weight. If the maximum weight is exceeded, the aircraft may not be able to achieve or sustain controlled, level flight. Excessive take-off weight may make it impossible to take off within available runway lengths, or it may completely prevent take-off. Excessive weight in flight may make climbing beyond a certain altitude difficult or impossible, or it may make it impossible to maintain an altitude.

 45-Shooter    PS. Part - II   3/17/2013 1:01:09 PM For trim adjustment of the tabs on the vertical and horizontal stabilizers. Yes I do know this, for how a plane is loaded determines how much preset angle of attack you must set for the control tabs to keep the nose pointed without too much rise in inclination (pitch) or side motion (called crabbing or yaw.). I also know that fuel use has more effect than a mere 1000 lb bomb on those presets, for a plane's center of gravity shifts constantly as consumables are burned off. This shows me that not only do you lie about the bombs, but you don't know what you read in the manuals, you claim you read. For if you did you would read the cautions in the Flying Fortress manuals about how to set trim to prevent yaw and in which order to use the fuel tanks to prevent an uncontrolled nose wander.   Now... you were claiming without proof again?  Please see this regulation manual on Weight and Balance from the FAA. While I do not know if the British-European regs are the same, I'll bet dollars against do-nuts that they are similar enough not to matter      Please!

oldbutnotwise       3/17/2013 2:36:11 PM
why did the recommended bomb drop sequence state nose to tail, this means that the final row of 3x 1000lbs were still attached when the row before was dropped, yet you claim that 1000lbs was enough to make the aircraft uncontrollable
I did not know this. I always thought it would be one from the back, one from the front, or Vice Verse untill they got to the centeral row of racks? But given the interval between the first and last bomb exiting the plane, it is easy to see why they do not have a problem with stability for that fraction of a second when the last bomb(s) is/are still on the hook, if it was the way you state.
so the sudden change was less of an issue that the constant force applied by a hung bomb! also having a

finally can you provide evidence of your statements as you seem to be the ONLY source of this information
OK, here we go again. I used the Range of CG limits as posted many times by others here as the starting point.
What CofG limits posted here I have not notice such a post and as you are so happy referencing it it shouldn't be a problem for you to post a link to it

Then I did a simple moment arm calc to see how far out of range the plane would be IF a 1000 pound bomb hung up in the last row. Since the results are very far out of permitted range, I concluded that what all the current pilot's manuals say about those sorts of things are true. See this;

CofG issuses were well known by the late 30s yet as I pointed out NO documents regarding the Lancaster refer to such an issue, and as the earlier models had a ventral turret that was discontinued in later models

#### Details of the Type R

```      Power system	     Electro-hydraulic system
Armament	     Two Browning 0.303in. Mk.II
Ammunition	     500 rounds per gun
Dia of turret ring   35in.
Field of fire	     Rotation 360°
Elevation 25°
Depression 90°
Gunsight       	     Wide angle periscope sight
Weight (empty)	     330lb (150kg)
Weight (armed)	     504lb (229kg)(+ 180lbs of gunner)	```
```      and this was as twice as far from the CofG as a 1000lbs hung bomb and it didn't cause an issue
```